This document defines basic operators and functions on the datatypes defined in
XQuery 1.0 and XPath 2.0 Functions and Operators has been defined through the efforts
of a joint task force of the
This document describes constructor functions, operators and functions that are used
in
This draft includes many corrections and changes based on member-only
and public comments on the
This draft is being provided to permit public review of the changes that have been made as a result of the Last Call comments. Publication as a Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.
Comments on the
changes should be made against the pertinent Last Call comment
(instructions can be found at
The XML Query and XSL Working Groups expect to progress this document to
The patent policy for this document is the
The purpose of this document is to catalog the functions and operators required for
XPath 2.0, XML Query 1.0 and XSLT 2.0. The exact syntax used to invoke these
functions and operators is specified in
This document defines constructor functions and functions that take typed values as
arguments. Some of the functions define the semantics of operators discussed in
References to specific sections of some of the above documents are indicated by
cross-document links in this document. Each such link consists of a pointer to a
specific section followed a superscript specifying the linked document. The
superscripts have the following meanings: 'XQ'
The Functions and Operators specification is intended primarily as a
component that can be used by other specifications. Therefore, Functions
and Operators relies on specifications that use it (such as
Authors of conformance criteria for the use of the Functions and Operators should pay particular attention to the following features:
Support for XML 1.0 and XML 1.1 by the datatypes used in Functions and Operators.
The functions and operators discussed in this document are contained in one of
four namespaces (see xs:QName
. Constructor functions for the built-in datatypes defined
in http://www.w3.org/2001/XMLSchema
,
and named in this document using the xs
prefix. The namespace
prefix used in this document for functions that are available to users is
fn
. Operator functions are named with the prefix op
.
The datatypes described in xdt
.
This document uses the prefix err
to represent the namespace URI http://www.w3.org/2005/xqt-errors
, which is the namespace for all XPath and XQuery error codes and messages. This namespace prefix is not predeclared and its use in this document is not normative.
The namespace prefix used for the functions, datatypes and errors can vary, as long as the prefix is bound to the correct URI.
The URIs of the namespaces and the default prefixes associated with them are:
http://www.w3.org/2001/XMLSchema
for constructors --
associated with xs
.
http://www.w3.org/2005/xpath-functions
for functions -- associated with fn
.
http://www.w3.org/2005/xpath-datatypes
for the datatypes -- associated with xdt
.
http://www.w3.org/2005/xqt-errors
-- associated with
err
.
The namespace URI associated with the err
prefix is not
expected to change from one version of this document to another. The
contents of this namespace may be extended to allow additional errors to be returned.
The functions defined with an fn
prefix are callable by the user.
Functions defined with the op
prefix are described here to
underpin the definitions of the operators in op
prefix. For example, multiplication is generally
associated with the *
operator, but it is described as a function
in this document:
In general, the specifications named above do not support function overloading
in the sense that functions that have multiple signatures with the same name and
the same number of parameters are not supported. Consequently, there are no such
overloaded functions in this document except for legacy fn:string()
, which accepts a single parameter of
a variety of types. In addition, it should be noted that the functions defined
in numeric
parameters accept arguments of type xs:integer
,
xs:decimal
, xs:float
or xs:double
. See
Each function is defined by specifying its signature, a description of the return type and each of the parameters and its semantics. For many functions, examples are included to illustrate their use.
Each function's signature is presented in a form like this:
In this notation, ()
"; otherwise, the name is followed by a parenthesized list of
parameter declarations, each declaration specifies the static type of the
parameter, in italics, and a descriptive, but non-normative, name. If there are
two or more parameter declarations, they are separated by a comma. The return-type
In some cases the word
is used in function signatures as a shorthand to indicate the four
numeric types: numeric
xs:integer
, xs:decimal
,
xs:float
and xs:double
. For example, a function with
the signature
For most functions there is an initial paragraph describing what the function does followed by semantic rules. These rules are meant to be followed in the order that they appear in this document.
In some cases, the static type returned by a function depends on the type(s) of
its argument(s). These special functions are indicated by using
The function name is a QName
as defined in fn:timezone-from-dateTime
.
Rules for passing parameters to operators are described in the relevant sections
of xdt:untypedAtomic
and the empty sequence are specified in this section.
As is customary, the parameter type name indicates that the function or operator
accepts arguments of that type, or types derived from it, in that position. This
is called
xs:anyURI
can be promoted to produce an argument
of the required type. (See xs:integer
may be used
where xs:decimal
is expected.xs:decimal
may be
promoted to xs:float
or xs:double
. Promotion to xs:double
should be done directly, not via xs:float
, to avoid loss of precision.
xs:anyURI
can be promoted to the
type xs:string
.
Some functions accept a single value or the empty sequence as an argument and
some may return a single value or the empty sequence. This is indicated in the
function signature by following the parameter or return type name with a
question mark: "?
", indicating that either a single value or the
empty sequence must appear. See below.
Note that this function signature is different from a signature in which the
parameter is omitted. See, for example, the two signatures
for fn:string()
. In the first signature, the parameter is omitted
and the argument defaults to the context item, referred to as .
.
In the second signature, the argument must be present but may be the empty
sequence, referred to as ().
Some functions accept a sequence of zero or more values as an argument. This is
indicated by following the name of type of the items in the sequence with
*
. The sequence may contain zero or more items of the named type.
For example, the function below accepts a sequence of xs:double
and
returns a xs:double
or the empty sequence.
This document uses the phrase "namespace URI" to identify the concept identified
in
It also uses the term expanded-QName
defined below.
An expanded-QName is a pair of values consisting of a namespace URI
and a local name. They belong to the value space of the xs:QName
. When this document
refers to xs:QName
we always mean the value space, i.e.
a namespace URI, local name pair (and not the lexical space
referring to constructs of the form prefix:local-name).
The diagram below shows the types for which functions are defined in this
document. These include the built-in types defined by xs:IDREFS
, xs:NMTOKENS
,
xs:ENTITIES
and user-defined list and union types
are
special types in that these types are lists or unions rather than true subtypes.
Dashed lines connect a union type above with its component types below.
The information in the above diagram is reproduced below in tabular form. For
ease of presentation the information is divided into three tables. The first
table shows the top three layers of the hierarchy starting at
xs:anyType
. The second table shows the types derived from
xdt:anyAtomicType
. The third table shows the types defined in
Each type whose name is indented is derived from the type whose name appears nearest above it with one less level of indentation.
xs:anyType | ||
user-defined complex types | ||
xdt:untyped | ||
xs:anySimpleType | ||
user-defined list and union types | ||
xs:IDREFS | ||
xs:NMTOKENS | ||
xs:ENTITIES | ||
xdt:anyAtomicType |
The table below shows the datatypes derived from xdt:anyAtomicType
.
This includes all the
Each type whose name is indented is derived from the type whose name appears nearest above it with one less level of indentation.
xdt:untypedAtomic | ||||||
xs:dateTime | ||||||
xs:date | ||||||
xs:time | ||||||
xs:duration | ||||||
xdt:yearMonthDuration | ||||||
xdt:dayTimeDuration | ||||||
xs:float | ||||||
xs:double | ||||||
xs:decimal | ||||||
xs:integer | ||||||
xs:nonPositiveInteger | ||||||
xs:negativeInteger | ||||||
xs:long | ||||||
xs:int | ||||||
xs:short | ||||||
xs:byte | ||||||
xs:nonNegativeInteger | ||||||
xs:unsignedLong | ||||||
xs:unsignedInt | ||||||
xs:unsignedShort | ||||||
xs:unsignedByte | ||||||
xs:positiveInteger | ||||||
xs:gYearMonth | ||||||
xs:gYear | ||||||
xs:gMonthDay | ||||||
xs:gDay | ||||||
xs:gMonth | ||||||
xs:string | ||||||
xs:normalizedString | ||||||
xs:token | ||||||
xs:language | ||||||
xs:NMTOKEN | ||||||
xs:Name | ||||||
xs:NCName | ||||||
xs:ID | ||||||
xs:IDREF | ||||||
xs:ENTITY | ||||||
xs:boolean | ||||||
xs:base64Binary | ||||||
xs:hexBinary | ||||||
xs:anyURI | ||||||
xs:QName | ||||||
xs:NOTATION |
The table below shows the type hierarchy for the types introduced in
item | |||
xdt:anyAtomicType | |||
node | |||
attribute | |||
user-defined attribute types | |||
comment | |||
document | |||
user-defined document types | |||
element | |||
user-defined element types | |||
processing-instruction | |||
text |
The terminology used to describe the functions and operators on
A feature of this specification included to ensure that
implementations that use this feature remain compatible with
Conforming documents and processors are permitted to, but need not, behave as described.
Conforming documents and processors are required to behave as described; otherwise, they are either non-conformant or else in error.
Possibly differing between implementations, but specified and documented by the implementor for each particular implementation.
Possibly differing between implementations, but not specified by this or other W3C specification, and not required to be specified by the implementor for any particular implementation.
The scope over which any two calls on a function would be executed. In XSLT, it applies to any two calls on the function executed during the same transformation. In XQuery, it applies to any two calls executed during the evaluation of a top-level expression i.e. an expression not contained in any other expression. In other contexts, the scope is specified by the host environment that invokes the function library.
Most of the functions in the core library have the property that
calling the same function twice within an fn:doc()
, fn:collection()
,
fn:current-dateTime()
, fn:current-date
and
fn:current-time()
whose result depends on the external
environment. Where the function returns nodes, stability means that
the returned nodes are identical, not merely equal and are returned
in the same order.. Some other functions, for example fn:position()
and fn:last(), depend on the dynamic context and may, therefore,
produce different results each time they are called. These functions
are said to be contextual.
Some other functions, for example fn:position()
and
fn:last()
, depend on the dynamic context and may,
therefore, produce different results each time they are called.
These functions are said to be
Within this specification, the term "URI" refers to Universal Resource Identifiers as
defined in xs:anyURI
datatype as defined in xs:anyURI
is a wider definition than the definition in
Accessors and their semantics are described in
Function | Accessor | Accepts | Returns |
---|---|---|---|
fn:node-name
|
node-name
|
an optional node | zero or one xs:QName
|
fn:nilled
|
nilled
|
a node | an optional xs:boolean
|
fn:string
|
string-value
|
an optional item or no argument |
xs:string
|
fn:data
|
typed-value
|
zero or more items | a sequence of atomic values |
fn:base-uri
|
base-uri
|
an optional node or no argument | zero or one xs:anyURI
|
fn:document-uri
|
document-uri
|
an optional node | zero or one xs:anyURI
|
Summary: Returns an expanded-QName for node kinds that can have names. For other
kinds of nodes it returns the empty sequence. If $arg
is the empty
sequence, the empty sequence is returned.
Summary: Returns an xs:boolean
indicating whether the argument node
is nilled
. If the argument is not an element node, returns the
empty sequence. If the argument is the empty sequence, returns the empty sequence.
Summary: Returns the value of $arg
represented as a
xs:string
. If no argument is supplied, this function returns the
string value of the context item (.
).
If no argument is supplied and the context item is undefined, an error is raised:
If $arg
is the empty sequence, the zero-length string is returned.
If $arg
is a node, the function returns the string-value of the
node, as obtained using the dm:string-value
accessor defined in the
If $arg
is an atomic value, then the function returns the same
string as is returned by the expression
(see $arg
cast as xs:string
Summary: fn:data
takes a sequence of items and returns a sequence of
atomic values.
The result of fn:data
is the sequence of atomic values produced by
applying the following rules to each item in $arg
:
If the item is an atomic value, it is returned.
If the item is a node:
If the node does not have a typed value an error is
raised
Otherwise, fn:data()
returns the typed value of the
node as defined by the accessor function
dm:typed-value
in
Summary: Returns the value of the base-uri property for $arg
as
defined by the accessor function dm:base-uri()
for that kind of
node in $arg
is not
specified, returns the value of the base-uri property of the context item
(.
) with the above semantics. If the context item is not a node, an
error is raised:
If $arg
is the empty sequence, the empty sequence is returned.
Document, element and processing-instruction nodes have a base-uri property which
may be empty. The base-uri property of all other node types is the empty
sequence. The value of the base-uri property is returned if it exists and is not
empty. Otherwise, if the node has a parent, the value of
dm:base-uri()
applied to its parent is returned, recursively. If
the node does not have a parent, or if the recursive ascent up the ancestor
chain encounters a node whose base-uri property is empty and it does not have a
parent, the empty sequence is returned.
See also fn:static-base-uri
.
Summary: Returns the value of the document-uri property for $arg
as
defined by the dm:document-uri
accessor function defined in
If $arg
is the empty sequence, the empty sequence is returned.
Returns the empty sequence if the node is not a document node. Otherwise, returns
the value of the dm:document-uri
accessor of the document node.
If fn:document-uri($arg)
does not return the empty sequence, then
the following expression always holds:
In this document, as well as in an error is raised
is used. Raising an error is equivalent to invoking the fn:error
function defined in this section with the provided error code.
The above phrase is normally accompanied by specification of a specific error, to
wit: an error is raised [
. Each error defined
in this document is identified by an xs:QName
that is in the
http://www.w3.org/2005/xqt-errors
namespace, represented in this document by the err
prefix. It is this
xs:QName
that is actually passed as an argument to the
fn:error
function invocation. Invocation of this function raises an error. For a
more detailed treatment of error handing, see
The fn:error
function is a general function that may be invoked as above
but may also be invoked from xs:QName
argument.
Summary: The fn:error
function raises an error. While this function never returns a value, an
error is returned to the external processing environment as an
xs:anyURI
or an xs:QName
. The error xs:anyURI
is derived from the error xs:QName
. An error xs:QName
with
namespace URI NS and local part LP will be returned as the xs:anyURI
NS#LP. The method by which the xs:anyURI
or xs:QName
is
returned to the external processing environment is
If an invocation provides $description
and $error-object
,
then these values may also be returned to the external processing environment. The
method by which these values are provided to the external environment is
The value of the $description
parameter may need to be localized.
Note that none
is a special type defined in
If fn:error
is invoked with no arguments, then its behavior is the same
as the invocation of the following expression:
If the first argument in the third or fourth signature is the empty sequence it is
assumed to be the xs:QName
constructed by:
fn:error()
returns
http://www.w3.org/2005/xqt-errors#FOER0000
to the
external processing environment.
fn:error(fn:QName('http://www.example.com/HR', 'myerr:toohighsal'),
'Does not apply because salary is too high')
returns
http://www.example.com/HR#toohighsal
and the xs:string
"Does not apply because salary is too high"
to the external
processing environment.
This function is intended to be used in debugging queries by providing a trace of their execution.
The input $value
is returned, unchanged, as the result of the function.
In addition, the inputs $value
, converted to an xs:string
,
and $label
may be directed to a trace data set. The destination of the
trace output is fn:trace()
function is
Consider a situation in which a user wants to investigate the actual
value passed to a function. Assume that in a particular execution,
$v
is an xs:decimal
with value
124.84
. Writing fn:trace($v, 'the value of $v
is:')
will put the strings "124.84"
and "the
value of $v is:"
in the trace data set in implementation
dependent order.
Every built-in atomic type that is defined in xs:NOTATION
, has an
associated constructor function; as do xdt:untypedAtomic
, defined
in xdt:yearMonthDuration
and xdt:dayTimeDuration
defined
in xs:NOTATION
since it is defined as an abstract type in xs:NOTATION
then a constructor function is defined for it.
See
The form of the constructor function for a type
If $arg
is the empty sequence, the empty sequence is returned. For
example, the signature of the constructor function corresponding to the
xs:unsignedInt
type defined in
Invoking the constructor function xs:unsignedInt(12)
returns
the xs:unsignedInt
value 12. Another invocation of that constructor
function that returns the same xs:unsignedInt
value is
xs:unsignedInt("12")
. The same result would also be returned if the
constructor function were to be invoked with a node that had a typed value equal
to the xs:unsignedInt
12. The standard features described in
The semantics of the constructor function
are identical to the semantics of xs:TYPE(arg)
, except for constructors for arg
cast as xs:TYPE?
xs:QName
and types derived from
xs:NOTATION
which are identical to cast as
. See xs:TYPE
If the argument to a constructor function is a literal, the result of the function may be evaluated statically; if an error is found during such evaluation, it may be reported as a static error.
Constructor functions for xs:QName
and
types derived from xs:QName
and xs:NOTATION
, are constrained to take a xs:string
literal as
their argument. (This means that they are actually pseudo-functions: they can
always be evaluated statically). A
static error is raised xs:QName
or a type derived from xs:QName
or xs:NOTATION
is not an xs:string
literal.
The prefix within the lexical xs:QName
supplied as the argument is resolved to a namespace URI using the statically
known namespaces from the static context. If the lexical xs:QName
has
no prefix, the namespace URI of the resulting expanded-QName is the default
element/type namespace from the static context. Components of the static context
are discussed in
The following constructor functions for the built-in types are supported:
Implementations xs:float("-0.0E0")
.
Implementations xs:double("-0.0E0").
$arg
must be a xs:string
literal.
See xs:ENTITY
and types derived from it.
A special constructor function is provided for constructing a
xs:dateTime
value from a xs:date
value and a
xs:time
value.
The result xs:dateTime
has a date component whose value is equal to
$arg1
and a time component whose value is equal
to $arg2
. The timezone of the result is computed as follows:
If neither argument has a timezone, the result has no timezone.
If exactly one of the arguments has a timezone, or if both arguments have the same timezone, the result has this timezone.
If the two arguments have different timezones, an error is
raised:
fn:dateTime(xs:date("1999-12-31"), xs:time("12:00:00"))
returns xs:dateTime("1999-12-31T12:00:00").
fn:dateTime(xs:date("1999-12-31"), xs:time("24:00:00"))
returns
xs:dateTime("1999-12-31T00:00:00")
because "24:00:00"
is an alternate lexical form for "00:00:00".
For every atomic type in the static context (See
Consider a situation where the static context contains a type
called hatSize
defined in a schema whose target namespace is bound
to the prefix my
. In such a case the constructor function:
is available to users.
To construct an instance of an atomic type that is not in a namespace, it is
necessary to use a cast expression or undeclare the default function namespace. For example, if the user-defined type apple
is derived
from xs:integer
but is not in a namespace, an instance of this type
can be constructed as follows using a cast expression (this requires that the
default element/type namespace is no namespace):
The following shows the use of the constructor function:
This section discusses arithmetic operators on the numeric datatypes defined in
The operators described in this section are defined on the following numeric types. Each type whose name is indented is derived from the type whose name appears nearest above with one less level of indentation.
xs:decimal | |
xs:integer | |
xs:float | |
xs:double |
They also apply to types derived by restriction from the above types.
This specification uses xs:float
and xs:double
values.
This differs from NaN
as being equal to itself and defines only a single zero in the value space while NaN
as unequal to all other values including itself and can produce distinct results of positive zero and negative zero. (These are two different machine representations for the same
The following functions define the semantics of operators defined in
Operators | Meaning |
---|---|
op:numeric-add
|
Addition |
op:numeric-subtract
|
Subtraction |
op:numeric-multiply
|
Multiplication |
op:numeric-divide
|
Division |
op:numeric-integer-divide
|
Integer division |
op:numeric-mod
|
Modulus |
op:numeric-unary-plus
|
Unary plus |
op:numeric-unary-minus
|
Unary minus (negation) |
The parameters and return types for the above operators are the basic numeric
types: xs:integer
, xs:decimal
, xs:float
and xs:double
, and types derived from them. The word
in function signatures signifies these four types. For simplicity, each
operator is defined to operate on operands of the same type and return the same
type. The exceptions are numeric
op:numeric-divide
, which returns
an xs:decimal
if called with two xs:integer
operands
and op:numeric-integer-divide
which always returns an xs:integer
.
If the two operands are not of the same type,
The result type of operations depends on their argument datatypes and is defined in the following table:
Operator | Returns |
---|---|
op:operation(xs:integer, xs:integer)
|
xs:integer (except for op:numeric-divide(integer,
integer) , which returns xs:decimal ) |
op:operation(xs:decimal, xs:decimal)
|
xs:decimal
|
op:operation(xs:float, xs:float)
|
xs:float
|
op:operation(xs:double, xs:double)
|
xs:double
|
op:operation(xs:integer)
|
xs:integer
|
op:operation(xs:decimal)
|
xs:decimal
|
op:operation(xs:float)
|
xs:float
|
op:operation(xs:double)
|
xs:double
|
These rules define any operation on any pair of arithmetic types. Consider the following example:
For this operation, xs:int
must be converted to
xs:double
. This can be done, since by the rules above:
xs:int
can be substituted for xs:integer
,
xs:integer
can be substituted for xs:decimal
,
xs:decimal
can be promoted to xs:double
. As far as possible, the promotions should be done in a
single step. Specifically, when an xs:decimal
is promoted to an
xs:double
, it should not be converted to an xs:float
and then to xs:double
, as this risks loss of precision.
As another example, a user may define height
as a derived type of
xs:integer
with a minimum value of 20 and a maximum value of 100.
He may then derive fenceHeight
using an enumeration to restrict the
permitted set of values to, say, 36, 48 and 60.
fenceHeight
can be substituted for its base type
height
and height
can be substituted for its base type
xs:integer
.
On overflow and underflow situations during arithmetic operations conforming
implementations
For xs:float
and xs:double
operations, overflow
behavior
Raising an error
Returning INF
or -INF
.
Returning the largest (positive or negative) non-infinite number.
For xs:float
and xs:double
operations,
underflow behavior
Raising an error
Returning 0.0E0
or +/- 2**Emin
or a
denormalized value; where Emin
is the smallest
possible xs:float
or xs:double
exponent.
For xs:decimal
operations, overflow behavior 0.0
must be returned.
For xs:integer
operations, implementations that support
limited-precision integer operations
They
They
The functions op:numeric-add
, op:numeric-subtract
,
op:numeric-multiply
, op:numeric-divide
,
op:numeric-integer-divide
and op:numeric-mod
are each
defined for pairs of numeric operands, each of which has the same
type:xs:integer
, xs:decimal
, xs:float
, or
xs:double
. The functions op:numeric-unary-plus
and
op:numeric-unary-minus
are defined for a single operand whose type
is one of those same numeric types.
For xs:float
and xs:double
arguments, if either
argument is NaN
, the result is NaN
.
For xs:decimal
values the number of digits of precision returned by
the numeric operators is
Summary: Backs up the "+" operator and returns the arithmetic sum of its
operands: ($arg1 + $arg2
).
For xs:float
or xs:double
values, if one of
the operands is a zero or a finite number and the other
is INF
or -INF
, INF
or
-INF
is returned. If both operands are INF
,
INF
is returned. If both operands are -INF
,
-INF
is returned. If one of the operands is
INF
and the other is -INF
, NaN
is returned.
Summary: Backs up the "-" operator and returns the arithmetic difference of
its operands: ($arg1 - $arg2
).
For xs:float
or xs:double
values, if one of
the operands is a zero or a finite number and the other
is INF
or -INF
, an infinity of the appropriate
sign is returned. If both operands are INF
or
-INF
, NaN
is returned. If one of the operands
is INF
and the other is -INF
, an infinity of
the appropriate sign is returned.
Summary: Backs up the "*" operator and returns the arithmetic product of its
operands: ($arg1 * $arg2
).
For xs:float
or xs:double
values, if one of
the operands is a zero and the other is an infinity, NaN
is
returned. If one of the operands is a non-zero number and the other
is an infinity, an infinity with the appropriate sign is returned.
Summary: Backs up the "div" operator and returns the arithmetic quotient of
its operands: ($arg1 div $arg2
).
As a special case, if the types of both $arg1
and
$arg2
are xs:integer
, then the return type is xs:decimal
.
For xs:decimal
and xs:integer
operands, if the
divisor is (positive or negative) zero, an error is raised xs:float
and xs:double
operands, floating point
division is performed as specified in
For xs:float
or xs:double
values, a positive
number divided by positive zero returns INF
. A negative number
divided by positive zero returns -INF
. Division by negative zero
returns -INF
and INF
, respectively. Positive or negative zero
divided by positive or negative zero returns NaN
. Also, INF
or -INF
divided
by INF
or -INF
returns NaN
.
Summary: This function backs up the "idiv" operator and performs an integer division: that is, it divides the first argument by the second, and returns the integer obtained by truncating the fractional part of the result. The division is performed so that the sign of the fractional part is the same as the sign of the dividend.
If the dividend, $arg1
, is not evenly divided by the divisor,
$arg2
, then the quotient is the xs:integer
value
obtained, ignoring (truncating) any remainder that results from the division
(that is, no rounding is performed). Thus, the semantics
are equivalent to $a idiv $b
except for error situations.($a div $b) cast as xs:integer
If the divisor is (positive or negative) zero, then an error is raised NaN
or if $arg1
is INF
or -INF
then
an error is raised
The semantics of this function are different from integer division as defined in programming languages such as Java and C++.
op:numeric-integer-divide(10,3)
returns 3
op:numeric-integer-divide(3,-2)
returns -1
op:numeric-integer-divide(-3,2)
returns -1
op:numeric-integer-divide(-3,-2)
returns 1
op:numeric-integer-divide(9.0,3)
returns 3
op:numeric-integer-divide(-3.5,3)
returns -1
op:numeric-integer-divide(3.0,4)
returns 0
op:numeric-integer-divide(3.1E1,6)
returns 5
op:numeric-integer-divide(3.1E1,7)
returns 4
Summary: Backs up the "mod" operator. Informally, this function returns the
remainder resulting from dividing $arg1
, the dividend, by
$arg2
, the divisor. The operation a mod b
for
operands that are xs:integer
or xs:decimal
, or
types derived from them, produces a result such that (a idiv b)*b+(a
mod b)
is equal to a
and the magnitude of the result
is always less than the magnitude of b
. This identity holds
even in the special case that the dividend is the negative integer of
largest possible magnitude for its type and the divisor is -1 (the remainder
is 0). It follows from this rule that the sign of the result is the sign of
the dividend.
For xs:integer
and xs:decimal
operands, if
$arg2
is zero, then an error is raised
For xs:float
and xs:double
operands the following
rules apply:
If either operand is NaN
, the result is NaN
.
If the dividend is positive or negative infinity, or the divisor is
positive or negative zero (0), or both, the result is NaN
.
If the dividend is finite and the divisor is an infinity, the result equals the dividend.
If the dividend is positive or negative zero and the divisor is finite, the result is the same as the dividend.
In the remaining cases, where neither positive or negative infinity,
nor positive or negative zero, nor NaN
is involved, the
result obeys (a idiv b)*b+(a mod b)
= a
.
Division is truncating division, analogous to integer division,
not
op:numeric-mod(10,3)
returns 1
.
op:numeric-mod(6,-2)
returns 0
.
op:numeric-mod(4.5,1.2)
returns 0.9
.
op:numeric-mod(1.23E2, 0.6E1)
returns 3.0E0
.
Summary: Backs up the unary "+" operator and returns its operand with the
sign unchanged: (+ $arg
). Semantically, this operation performs
no operation.
Summary: Backs up the unary "-" operator and returns its operand with the
sign reversed: (- $arg
). If $arg
is positive, its
negative is returned; if it is negative, its positive is returned.
For xs:integer
and xs:decimal
arguments,
0
and 0.0
return 0
and
0.0
, respectively. For xs:float
and
xs:double
arguments, NaN
returns NaN
,
0.0E0
returns -0.0E0
and vice versa.
INF
returns -INF
. -INF
returns INF
.
This specification defines the following comparison operators on numeric values.
Comparisons take two arguments of the same type. If the arguments are of
different types, one argument is promoted to the type of the other as described
above in NaN
, false
is
returned.
Operator | Meaning |
---|---|
op:numeric-equal
|
Equality comparison |
op:numeric-less-than
|
Less-than comparison |
op:numeric-greater-than
|
Greater-than comparison |
Summary: Returns true if and only if the value of $arg1
is equal
to the value of $arg2
. For xs:float
and
xs:double
values, positive zero and negative zero compare
equal. INF
equals INF
and -INF
equals
-INF
. NaN
does not equal itself.
This function backs up the "eq", "ne", "le" and "ge" operators on numeric values.
Summary: Returns true
if and only if $arg1
is less
than $arg2
. For xs:float
and
xs:double
values, positive infinity is greater than all other
non-NaN
values; negative infinity is less than all other
non-NaN
values. If $arg1
or $arg2
is
NaN
, the function returns false
.
This function backs up the "lt" and "le" operators on numeric values.
Summary: Returns true
if and only if $arg1
is
greater than $arg2
. For xs:float
and
xs:double
values, positive infinity is greater than all other
non-NaN
values; negative infinity is less than all other
non-NaN
values. If $arg1
or $arg2
is
NaN
, the function returns false
.
This function backs up the "gt" and "ge" operators on numeric values.
The following functions are defined on numeric types. Each function returns a value of the same type as the type of its argument.
If the argument is the empty sequence, the empty sequence is returned.
For xs:float
and xs:double
arguments, if the
argument is "NaN", "NaN" is returned.
Except for fn:abs()
, for xs:float
and
xs:double
arguments, if the argument is positive or
negative infinity, positive or negative infinity is returned.
Function | Meaning |
---|---|
fn:abs
|
Returns the absolute value of the argument. |
fn:ceiling
|
Returns the smallest number with no fractional part that is greater than or equal to the argument. |
fn:floor
|
Returns the largest number with no fractional part that is less than or equal to the argument. |
fn:round
|
Rounds to the nearest number with no fractional part. |
fn:round-half-to-even
|
Takes a number and a precision and returns a number rounded to the given precision. If the fractional part is exactly half, the result is the number whose least significant digit is even. |
Summary: Returns the absolute value of $arg
. If
$arg
is negative returns -$arg
otherwise returns
$arg
. If type of $arg
is one of the four numeric
types xs:float
, xs:double
, xs:decimal
or xs:integer
the type of the result is the same as the type of
$arg
. If the type of $arg
is a type derived from
one of the numeric types, the result is an instance of the base numeric type.
For xs:float
and xs:double
arguments, if the
argument is positive zero or negative zero, then positive zero
is returned. If the argument is positive or negative infinity, positive
infinity is returned.
For detailed type semantics, see
fn:abs(10.5)
returns 10.5
.
fn:abs(-10.5)
returns 10.5
.
Summary: Returns the smallest (closest to negative infinity) number with no
fractional part that is not less than the value of $arg
. If
type of $arg
is one of the four numeric types
xs:float
, xs:double
, xs:decimal
or
xs:integer
the type of the result is the same as the type of
$arg
. If the type of $arg
is a type derived from
one of the numeric types, the result is an instance of the base numeric type.
For xs:float
and xs:double
arguments, if the
argument is positive zero, then positive zero is returned. If the
argument is negative zero, then negative zero is returned. If the
argument is less than zero and greater than -1, negative zero is returned.
For detailed type semantics, see
fn:ceiling(10.5)
returns 11
.
fn:ceiling(-10.5)
returns -10
.
Summary: Returns the largest (closest to positive infinity) number with no
fractional part that is not greater than the value of $arg
. If
type of $arg
is one of the four numeric types
xs:float
, xs:double
, xs:decimal
or
xs:integer
the type of the result is the same as the type of
$arg
. If the type of $arg
is a type derived from
one of the numeric types, the result is an instance of the base numeric type.
For float
and double
arguments, if the argument is
positive zero, then positive zero is returned. If the argument is
negative zero, then negative zero is returned.
For detailed type semantics, see
fn:floor(10.5)
returns 10
.
fn:floor(-10.5)
returns -11
.
Summary: Returns the number with no fractional part that is closest to the
argument. If there are two such numbers, then the one that is closest to
positive infinity is returned. If type of $arg
is one of the
four numeric types xs:float
, xs:double
,
xs:decimal
or xs:integer
the type of the result is
the same as the type of $arg
. If the type of $arg
is a type derived from one of the numeric types, the result is an instance
of the base numeric type.
For xs:float
and xs:double
arguments, if the
argument is positive infinity, then positive infinity is returned. If the
argument is negative infinity, then negative infinity is returned. If the
argument is positive zero, then positive zero is returned. If the
argument is negative zero, then negative zero is returned. If the
argument is less than zero, but greater than or equal to -0.5, then
negative zero is returned. In the cases where positive zero or negative zero is returned, negative zero or positive zero may be returned as
For the last two cases, note that the result is not the same as fn:floor(x+0.5)
.
For detailed type semantics, see
fn:round(2.5)
returns 3.
fn:round(2.4999)
returns 2
.
fn:round(-2.5)
returns -2
(not the
possible alternative, -3
).
Summary: The value returned is the nearest (that is, numerically closest)
numeric to $arg
that is a multiple of ten to the power of minus
$precision
. If two such values are equally near (e.g. if the
fractional part in $arg
is exactly .500...), returns the one
whose least significant digit is even. If type of $arg
is one
of the four numeric types xs:float
, xs:double
,
xs:decimal
or xs:integer
the type of the result is
the same as the type of $arg
. If the type of $arg
is a type derived from one of the numeric types, the result is an instance
of the base numeric type.
The first signature of this function produces the same result as the second
signature with $precision=0
.
For arguments of type xs:float
and xs:double
, if
the argument is positive zero, then positive zero is returned. If
the argument is negative zero, then negative zero is returned. If
the argument is less than zero, but greater than or equal to -0.5, then
negative zero is returned.
If $arg
is of type xs:float
or xs:double
, rounding occurs on the value of the mantissa
computed with exponent = 0.
For detailed type semantics, see
fn:round-half-to-even(0.5)
returns 0
.
fn:round-half-to-even(1.5)
returns 2
.
fn:round-half-to-even(2.5)
returns 2
.
fn:round-half-to-even(3.567812E+3, 2)
returns 3567.81E0
.
fn:round-half-to-even(4.7564E-3, 2)
returns
0.0E0
.
fn:round-half-to-even(35612.25, -2)
returns
35600
.
This section discusses functions and operators on the xs:string
datatype and the datatypes derived from it.
The operators described in this section are defined on the following types. Each type whose name is indented is derived from the type whose name appears nearest above with one less level of indentation.
xs:string | |||||
xs:normalizedString | |||||
xs:token | |||||
xs:language | |||||
xs:NMTOKEN | |||||
xs:Name | |||||
xs:NCName | |||||
xs:ID | |||||
xs:IDREF | |||||
xs:ENTITY |
They also apply to user-defined types derived by restriction from the above types.
It is
Unless explicitly stated, the xs:string
values returned by the
functions in this document are not normalized in the sense of
This document uses the term "code point", sometimes spelt "codepoint" (also known as "character number" or "code position") to mean a non-negative integer that represents a character in some encoding. See
In functions that involve character counting such
as fn:substring
, fn:string-length
and
fn:translate
, what is counted is the number of XML characters
in the string (or equivalently, the number of Unicode code points). Some
implementations may represent a code point above xFFFF using two 16-bit
values known as a surrogate. A surrogate counts as one character, not two.
Function | Meaning |
---|---|
fn:codepoints-to-string
|
Creates an xs:string from a sequence of Unicode code points. |
fn:string-to-codepoints
|
Returns the sequence of Unicode code points that constitute an
xs:string . |
Summary: Creates an xs:string
from a sequence of $arg
is the empty sequence. If any of the
code points in $arg
is not a legal XML character, an error is
raised
fn:codepoints-to-string((2309, 2358, 2378, 2325))
returns "अशॊक"
Summary: Returns the sequence of xs:string
. If $arg
is a zero-length string or the
empty sequence, the empty sequence is returned.
fn:string-to-codepoints("Thérèse")
returns the sequence (84, 104, 233, 114, 232, 115, 101)
A collation is a specification of the manner in which character strings are
compared and, by extension, ordered. When values whose type is
xs:string
or a type derived from xs:string
are
compared (or, equivalently, sorted), the comparisons are inherently
performed according to some collation (even if that collation is defined
entirely on code point values). The
Collations can indicate that two different code points are, in fact, equal for comparison purposes (e.g., "v" and "w" are considered equivalent in Swedish). Strings can be compared codepoint-by-codepoint or in a linguistically appropriate manner, as defined by the collation.
Some collations, especially those based on the http://www.w3.org/2005/xpath-functions/collation/codepoint
,
provides the ability to compare strings based on code point values. Every
implementation of XQuery/XPath must support the collation based on code
point values.
In the ideal case, a collation should treat two strings as equal if the two strings are identical after Unicode normalization. Thus, the
This specification assumes that collations are named and that the collation
name may be provided as an argument to string functions. Functions that
allow specification of a collation do so with an argument whose type is
xs:string
but whose lexical form must conform to an
xs:anyURI
. If the collation is specified using a relative URI,
it is assumed to be relative to the value of the base-uri property in the
static context. This specification also defines the manner in which a
default collation is determined if the collation argument is not specified
in invocations of functions that use a collation but allow it to be omitted.
This specification does not define whether or not the collation URI is
dereferenced. The collation URI may be an abstract identifier, or it may
refer to an actual resource describing the collation. If it refers to a
resource, this specification does not define the nature of that resource.
One possible candidate is that the resource is a locale description
expressed using the Locale Data Markup Language: see
Functions such as fn:compare
and fn:max
that
compare xs:string
values use a single collation URI to identify
all aspects of the collation rules. This means that any parameters such as
the strength of the collation must be specified as part of the collation
URI. For example, suppose there is a collation
that refers to a French collation that compares on the basis of
base characters. Collations that use the same basic rules, but with higher
strengths, for example, base characters and accents, or base characters,
accents and case, would need to be given different names, say http://www.example.com/collations/French
and http://www.example.com/collations/French1
. Note that some specifications use the term collation to refer to
an algorithm that can be parameterized, but in this specification, each
possible parameterization is considered to be a distinct collation.http://www.example.com/collations/French2
The XQuery/XPath static context includes a provision for a default collation
that can be used for string comparisons and ordering operations. See the
description of the static context in http://www.w3.org/2005/xpath-functions/collation/codepoint
).
The decision of which collation to use for a given comparison or ordering function is determined by the following algorithm:
If the function specifies an explicit collation, CollationA (e.g., if
the optional collation argument is specified in an invocation of the
fn:compare()
function), then:
If CollationA is supported by the implementation, then CollationA is used.
Otherwise, an error is raised
If no collation is explicitly specified for the function and the default collation in the XQuery/XPath static context is CollationB, then:
If CollationB is supported by the implementation, then CollationB is used.
Otherwise, an error is raised
XML allows elements to specify the xml:lang
attribute to
indicate the language associated with the content of such an element.
This specification does not use xml:lang
to identify the
default collation
because using
xml:lang
does not produce desired effects when the two
strings to be compared have different xml:lang
values or
when a string is multilingual.
Function | Meaning | |
---|---|---|
fn:compare
|
Returns -1, 0, or 1, depending on whether the value of the first argument is respectively less than, equal to, or greater than the value of the second argument, according to the rules of the collation that is used. | |
fn:codepoint-equal
|
Returns true if the two arguments are equal using
the Unicode code point collation. |
Summary: Returns -1, 0, or 1, depending on whether the value of the
$comparand1
is respectively less than, equal to, or greater
than the value of $comparand2
, according to the rules of the
collation that is used.
The collation used by the invocation of this function is determined according
to the rules in
If either argument is the empty sequence, the result is the empty sequence.
This function, invoked with the first signature, backs up the "eq", "ne", "gt", "lt", "le" and "ge" operators on string values.
fn:compare('abc', 'abc')
returns 0.
fn:compare('Strasse', 'Straße')
returns 0
if and only if the default collation includes provisions that
equate ss
and the (German) character
ß
(sharp-s
). (Otherwise,
the returned value depends on the semantics of the default collation.)
fn:compare('Strasse', 'Straße', 'deutsch')
returns 0 if the collation identified by the relative URI
constructed from the string
value
deutsch
includes provisions that equate
ss
and the (German) character
ß
(sharp-s
). (Otherwise,
the returned value depends on the semantics of that collation.)
fn:compare('Strassen', 'Straße')
returns 1
if the default collation includes provisions that treat
differences between ss
and the (German) character
ß
(sharp-s
) with less
strength than the differences between the base characters, such
as the final n
.
Summary: Returns true
or false
depending on whether
the value of $comparand1
is equal to the value of
$comparand2
, according to the Unicode code point collation (http://www.w3.org/2005/xpath-functions/collation/codepoint
).
If either argument is the empty sequence, the result is the empty sequence.
This function allows xs:anyURI
values to be compared without having to specify the Unicode code point collation.
The following functions are defined on values of type xs:string
and
types derived from it.
Function | Meaning |
---|---|
fn:concat
|
Concatenates two or more xdt:anyAtomicType arguments
cast to xs:string . |
fn:string-join
|
Returns the xs:string produced by concatenating a
sequence of xs:string s using an optional separator. |
fn:substring
|
Returns the xs:string located at a specified place
within an argument xs:string . |
fn:string-length
|
Returns the length of the argument. |
fn:normalize-space
|
Returns the whitespace-normalized value of the argument. |
fn:normalize-unicode
|
Returns the normalized value of the first argument in the normalization form specified by the second argument. |
fn:upper-case
|
Returns the upper-cased value of the argument. |
fn:lower-case
|
Returns the lower-cased value of the argument. |
fn:translate
|
Returns the first xs:string argument with occurrences
of characters contained in the second argument replaced by the
character at the corresponding position in the third argument. |
fn:encode-for-uri
|
Returns the xs:string argument with certain characters escaped to enable the resulting string to be used as a path segment in a URI. |
fn:iri-to-uri
|
Returns the xs:string argument with certain characters escaped to enable the resulting string to be used as (part of) a URI. |
fn:escape-html-uri
|
Returns the xs:string argument with certain characters escaped in the manner that html user agents handle attribute values that expect URIs. |
When the above operators and functions are applied to datatypes derived from
xs:string
, they are guaranteed to return legal
xs:string
s, but they might not return a legal value for the
particular subtype to which they were applied.
The strings returned by fn:concat
and fn:string-join
are not guaranteed to be normalized. But see note in fn:concat
.
Summary: Accepts two or more xdt:anyAtomicType
arguments and
casts them to xs:string
. Returns the xs:string
that is the concatenation of the values of its arguments after conversion.
If any of the arguments is the empty sequence, the argument is treated as
the zero-length string.
The fn:concat
function is specified to allow an two or more
arguments that are concatenated together. This is the only function
specified in this document that allows a variable number of arguments. This
capability is retained for compatibility with
As mentioned in the note above, the result of fn:concat
may not be normalized. If a normalized result is required, fn:normalize-unicode
can be applied to the xs:string
returned by fn:concat
. The following XQuery:
where the "?" represents either the actual Unicode character COMBINING DIARESIS (Unicode codepoint U+0308) or "̈", will return:
"I plan to go to Mu?nchen in September"
where the "?" represents either the actual Unicode character COMBINING DIARESIS (Unicode codepoint U+0308) or "̈". It is worth noting that the returned value is not normalized in NFC; however, it is normalized in NFD. .
However, the following XQuery:
where the "?" represents either the actual Unicode character COMBINING DIARESIS (Unicode codepoint U+0308) or "̈", will return:
"I plan to go to München in September"
This returned result is normalized in NFC.
fn:concat('un', 'grateful')
returns
. ungrateful
fn:concat('Thy ', (), 'old ', "groans", "", ' ring', '
yet', ' in', ' my', ' ancient',' ears.')
returns
. Thy old groans ring yet in my ancient ears.
fn:concat('Ciao!',())
returns
. Ciao!
fn:concat('Ingratitude, ', 'thou ', 'marble-hearted', '
fiend!')
returns
. Ingratitude, thou marble-hearted fiend!
Summary: Returns a xs:string
created by concatenating the
members of the $arg1
sequence using $arg2
as a
separator. If the value of $arg2
is the zero-length string,
then the members of $arg1
are concatenated without a separator.
If the value of $arg1
is the empty sequence, the zero-length
string is returned.
fn:string-join(('Now', 'is', 'the', 'time', '...'), '
')
returns
. Now is the time ...
fn:string-join(('Blow, ', 'blow, ', 'thou ', 'winter ',
'wind!'), '')
returns
. Blow, blow, thou winter wind!
fn:string-join((), 'separator')
returns .
Assume a document:
with the <section>
as the context node,
the
fn:string-join(for $n in ancestor-or-self::* return
name($n), '/')
returns
doc/chap/section
Summary: Returns the portion of the value of $sourceString
beginning at the position indicated by the value of
$startingLoc
and continuing for the number of characters
indicated by the value of $length
. The characters returned do
not extend beyond $sourceString
. If $startingLoc
is zero or negative, only those characters in positions greater than zero
are returned.
More specifically, the three argument version of the function returns the
characters in $sourceString
whose position $p
obeys:
fn:round($startingLoc) <= $p < fn:round($startingLoc) + fn:round($length)
The two argument version of the function assumes that $length
is
infinite and returns the characters in $sourceString
whose
position $p
obeys:
fn:round($startingLoc) <= $p < fn:round(INF)
In the above computations, the rules for op:numeric-less-than()
and op:numeric-greater-than()
apply.
If the value of $sourceString
is the empty sequence, the
zero-length string is returned.
The first character of a string is located at position 1, not position 0.
fn:substring("motor car", 6)
returns " car"
.
Characters starting at position 6 to the end of
$sourceString
are selected.
fn:substring("metadata", 4, 3)
returns "ada"
.
Characters at positions greater than or equal to 4 and less than 7 are selected.
fn:substring("12345", 1.5, 2.6)
returns "234"
.
Characters at positions greater than or equal to 2 and less than 5 are selected.
fn:substring("12345", 0, 3)
returns "12"
.
Characters at positions greater than or equal to 0 and less than 3 are selected. Since the first position is 1, these are the characters at positions 1 and 2.
fn:substring("12345", 5, -3)
returns ""
.
Characters at positions greater than or equal to 5 and less than 2 are selected.
fn:substring("12345", -3, 5)
returns "1"
.
Characters at positions greater than or equal to -3 and less than 2 are selected. Since the first position is 1, this is the character at position 1.
fn:substring("12345", 0 div 0E0, 3)
returns ""
.
Since 0 div 0E0
returns NaN
, and
NaN
compared to any other number returns
false
, no characters are selected.
fn:substring("12345", 1, 0 div 0E0)
returns ""
.
As above.
fn:substring((), 1, 3)
returns ""
.
fn:substring("12345", -42, 1 div 0E0)
returns "12345"
.
Characters at positions greater than or equal to -42 and less than INF are selected.
fn:substring("12345", -1 div 0E0, 1 div 0E0)
returns ""
.
Since -INF + INF
returns NaN
, no
characters are selected.
Summary: Returns an xs:integer
equal to the length in characters
of the value of $arg
.
If the value of $arg
is the empty sequence, the
xs:integer
0 is returned.
If no argument is supplied, $arg
defaults to the string value
(calculated using fn:string()
) of the context item
(.
). If no argument is supplied and the context item is
undefined an error is raised:
fn:string-length("Harp not on that string, madam; that is
past.")
returns 45
.
fn:string-length(())
returns 0
.
Summary: Returns the value of $arg
with whitespace normalized by
stripping leading and trailing whitespace and replacing sequences of one or
more than one whitespace character with a single space, #x20
.
The whitespace characters are defined in the metasymbol S (Production 3)
of
The definition of the metasymbol S (Production 3), is unchanged
in
If the value of
$arg
is the empty sequence, returns the zero-length string.
If no argument is supplied, $arg
defaults to the string value
(calculated using fn:string()
) of the context item
(.
). If no argument is supplied and the context item is
undefined an error is raised:
fn:normalize-space(" The wealthy curled darlings
of our nation. ")
returns
. The wealthy curled darlings of our nation.
fn:normalize-space(())
returns .
Summary: Returns the value of $arg
normalized according to the
normalization criteria for a normalization form identified by the value of
$normalizationForm
. The effective value of the
$normalizationForm
is computed by removing leading and trailing
blanks, if present, and converting to upper case.
If the value of $arg
is the empty sequence, returns the
zero-length string.
See
If the $normalizationForm
is absent, as in the first format
above, it shall be assumed to be "NFC"
If the effective value of $normalizationForm
is
NFC
, then the value returned by the function is the
value of $arg
in Unicode Normalization Form C (NFC).
If the effective value of $normalizationForm
is
NFD
, then the value returned by the function is the
value of $arg
in Unicode Normalization Form D (NFD).
If the effective value of $normalizationForm
is
NFKC
, then the value returned by the function is the
value of $arg
in Unicode Normalization Form KC (NFKC).
If the effective value of $normalizationForm
is
NFKD
, then the value returned by the function is the
value of $arg
in Unicode Normalization Form KD (NFKD).
If the effective value of $normalizationForm
is
FULLY-NORMALIZED
, then the value returned by the
function is the value of $arg
in the fully normalized form.
If the effective value of $normalizationForm
is the
zero-length string, no normalization is performed and
$arg
is returned.
Conforming implementations $normalizationForm
is other than
one of the values supported by the implementation, then an error is raised
Summary: Returns the value of $arg
after translating every
character to its upper-case correspondent as defined in the Unicode standard
If the value of $arg
is the empty sequence, the zero-length
string is returned.
Case mappings may change the length of a string. In general, the two
functions are not inverses of each other
fn:lower-case(fn:upper-case($arg))
is not guaranteed to
return $arg
, nor
is fn:upper-case(fn:lower-case($arg))
. The Latin small
letter dotless i (as used in Turkish) is perhaps the most prominent
lower-case letter which will not round-trip. The Latin capital letter i
with dot above is the most prominent upper-case letter which will not
round trip; there are others.
These functions may not always be linguistically appropriate (e.g. Turkish i without dot) or appropriate for the application (e.g. titlecase). In cases such as Turkish, a simple translation should be used first.
Results may violate user expectations (in Quebec, for example, the standard uppercase equivalent of "è" is "È", while in metropolitan France it is more commonly "E"; only one of these is supported by the functions as defined).
Many characters of class Ll lack uppercase equivalents in the Unicode case mapping tables; many characters of class Lu lack lowercase equivalents.
fn:upper-case("abCd0")
returns
"ABCD0"
.
Summary: returns the value of $arg
after translating every
character to its lower-case correspondent as defined in the Unicode standard
If the value of $arg
is the empty sequence, the zero-length
string is returned.
Case mappings may change the length of a string. In general, the two
functions are not inverses of each other
fn:lower-case(fn:upper-case($arg))
is not guaranteed to
return $arg
, nor
is fn:upper-case(fn:lower-case($arg))
. The Latin small
letter dotless i (as used in Turkish) is perhaps the most prominent
lower-case letter which will not round-trip. The Latin capital letter i
with dot above is the most prominent upper-case letter which will not
round trip; there are others.
These functions may not always be linguistically appropriate (e.g. Turkish i without dot) or appropriate for the application (e.g. titlecase). In cases such as Turkish, a simple translation should be used first.
Results may violate user expectations (in Quebec, for example, the standard uppercase equivalent of "è" is "È", while in metropolitan France it is more commonly "E"; only one of these is supported by the functions as defined).
Many characters of class Ll lack uppercase equivalents in the Unicode case mapping tables; many characters of class Lu lack lowercase equivalents.
fn:lower-case("ABc!D")
returns
"abc!d"
.
Summary: Returns the value of $arg
modified so that every
character in the value of $arg
that occurs at some position
$mapString
has been replaced by
the character that occurs at position $transString
.
If the value of $arg
is the empty sequence, the zero-length
string is returned.
Every character in the value of $arg
that does not appear in the
value of $mapString
is unchanged.
Every character in the value of $arg
that appears at some
position $mapString
, where the
value of $transString
is less than $mapString
is
the zero-length string $arg
is returned.
If a character occurs more than once in $mapString
, then the
first occurrence determines the replacement character. If
$transString
is longer than $mapString
, the excess
characters are ignored.
fn:translate("bar","abc","ABC")
returns "BAr"
fn:translate("--aaa--","abc-","ABC")
returns "AAA"
.
fn:translate("abcdabc", "abc", "AB")
returns
"ABdAB"
.
Summary: This function should be used to process an xs:string
to be used as a path segment in a URI. It is invertible but not idempotent. This function applies the URI escaping rules defined in section 2 of
$uri-part
. The effect of the
function is to escape a set of identified characters in the string. Each
such character is replaced in the string by an escape sequence, which is
formed by encoding the character as a sequence of octets in UTF-8, and then
representing each of these octets in the form %HH, where HH is the
hexadecimal representation of the octet.
If $uri-part
is the empty sequence, returns the zero-length string.
All characters are escaped other than the lower case letters a-z, the upper case letters A-Z, the digits 0-9, the NUMBER SIGN "#" and HYPHEN-MINUS ("-"), LOW LINE ("_"), FULL STOP ".", EXCLAMATION MARK "!", TILDE "~", ASTERISK "*", APOSTROPHE "'", LEFT PARENTHESIS "(", and RIGHT PARENTHESIS ")".
Since
fn:encode-for-uri
("http://www.example.com/00/Weather/CA/Los%20Angeles#ocean")
returns "http%3A%2F%2Fwww.example.com%2F00%2FWeather%2FCA%2FLos%2520Angeles#ocean"
. This is probably not what the user wants as the '%' sign in the percent-encoded space character is escaped.
concat("http://www.example.com/", encode-for-uri("~bébé")) returns "http://www.example.com/~b%C3%A9b%C3%A9"
.
concat("http://www.example.com/", encode-for-uri("100% organic")) returns "http://www.example.com/100%25%20organic"
.
Summary: This function should be used to process an xs:string
to be used as a URI or part of a URI. It is idempotent but not invertible. This function applies the URI escaping rules defined in section 2 of
$uri-part
, which typically
represents all or part of a URI. The effect of the
function is to escape a set of identified characters in the string. Each
such character is replaced in the string by an escape sequence, which is
formed by encoding the character as a sequence of octets in UTF-8, and then
representing each of these octets in the form %HH, where HH is the
hexadecimal representation of the octet.
If $uri-part
is the empty sequence, returns the zero-length string.
All characters are escaped other than the lower case letters a-z, the upper case letters A-Z, the digits 0-9, the NUMBER SIGN "#" and HYPHEN-MINUS ("-"), LOW LINE ("_"), FULL STOP ".", EXCLAMATION MARK "!", TILDE "~", ASTERISK "*", APOSTROPHE "'", LEFT PARENTHESIS "(", and RIGHT PARENTHESIS ")", SEMICOLON ";", SOLIDUS "/", QUESTION MARK "?", COLON ":", COMMERCIAL AT "@", AMPERSAND "&", EQUALS SIGN "=", PLUS SIGN "+", DOLLAR SIGN "$", COMMA ",", LEFT SQUARE BRACKET "[", RIGHT SQUARE BRACKET "]", and the PERCENT SIGN "%".
Since
Since this function does not escape the PERCENT SIGN "%" and this character is not allowed in data within a URI, users wishing to convert character strings, such as file names, that include "%" to a URI should manually escape "%" by replacing it with "%25".
fn:iri-to-uri
("http://www.example.com/00/Weather/CA/Los%20Angeles#ocean")
returns "http://www.example.com/00/Weather/CA/Los%20Angeles#ocean"
.
fn:iri-to-uri
("http://www.example.com/~bébé")
returns "http://www.example.com/~b%C3%A9b%C3%A9"
.
Summary: This function escapes all characters except printable characters of the US-ASCII coded character set, specifically the octets ranging from 32 to 126 (decimal). The effect of the function is to escape a URI in the manner html user agents handle attribute values that expect URIs. Each character in $uri
to be escaped is replaced by an escape sequence, which is formed by encoding the character as a sequence of octets in UTF-8, and then representing each of these octets in the form %HH, where HH is the hexadecimal representation of the octet. This function must always generate hexadecimal values using the upper-case letters A-F.
If $uri
is the empty sequence, returns the zero-length string.
The behavior of this function corresponds to the recommended handling
of non-ASCII characters in URI attribute values as described in
fn:escape-html-uri
("http://www.example.com/00/Weather/CA/Los Angeles#ocean")
returns "http://www.example.com/00/Weather/CA/Los Angeles#ocean"
.
fn:escape-html-uri
("javascript:if (navigator.browserLanguage == 'fr') window.open('http://www.example.com/~bébé');") returns "javascript:if (navigator.browserLanguage == 'fr') window.open('http://www.example.com/~b%C3%A9b%C3%A9');")
.
The functions described in the section examine a string $arg1
to see
whether it contains another string $arg2
as a substring. The result
depends on whether $arg2
is a substring of $arg1
, and
if so, on the range of characters in $arg1
which $arg2
matches.
When the Unicode code point collation
is used, this simply involves determining whether $arg1
contains a
contiguous sequence of characters whose code points are the same, one for one,
with the code points of the characters in $arg2
.
When a collation is specified, the rules are more complex.
All collations support the capability of deciding whether two strings are
considered equal, and if not, which of the strings should be regarded as
preceding the other. For functions such as fn:compare()
, this is
all that is required. For other functions, such as fn:contains()
,
the collation needs to support an additional property: it must be able to
decompose the string into a sequence of collation units, each unit consisting of
one or more characters, such that two strings can be compared by pair wise
comparison of these units. ("collation unit" is equivalent to "collation
element" as defined in $arg1
is then considered to contain $arg2
as a
substring if the sequence of collation units corresponding to $arg2
is a subsequence of the sequence of the collation units corresponding to
$arg1
. The characters in $arg1
that match are the
characters corresponding to these collation units.
This rule may occasionally lead to surprises. For example, consider a collation
that treats "Jaeger" and "Jäger" as equal. It might do this by
treating "ä" as representing two collation units, in which case the
expression fn:contains("Jäger", "eg")
will return
true
. Alternatively, a collation might treat "ae" as a single
collation unit, in which case the expression fn:contains("Jaeger",
"eg")
will return false
. The results of these functions thus
depends strongly on the properties of the collation that is used. In addition,
collations may specify that some collation units should be ignored during matching.
In the definitions below, we say that $arg1
contains
$arg2
at positions m
through n
if the
collation units corresponding to characters in positions m
to
n
of $arg1
are the same as the collation units
corresponding to all the characters of $arg2
modulo ignorable
collation units. In the simple case of the Unicode code point collation, the
collation units are the same as the characters of the string. See
It is possible to define collations that do not have the ability to decompose a
string into units suitable for substring matching. An argument to a function
defined in this section may be a URI that identifies a collation that is able to
compare two strings, but that does not have the capability to split the string
into collation units. Such a collation may cause the function to fail, or to
give unexpected results or it may be rejected as an unsuitable argument. The
ability to decompose strings into collation units is an
Function | Meaning |
---|---|
fn:contains
|
Indicates whether one xs:string contains another
xs:string . A collation may be specified. |
fn:starts-with
|
Indicates whether the value of one xs:string begins
with the collation units of another xs:string . A
collation may be specified. |
fn:ends-with
|
Indicates whether the value of one xs:string ends with
the collation units of another xs:string . A collation
may be specified. |
fn:substring-before
|
Returns the collation units of one xs:string that
precede in that xs:string the collation units of
another xs:string . A collation may be specified. |
fn:substring-after
|
Returns the collation units of xs:string that follow in
that xs:string the collation units of another
xs:string . A collation may be specified. |
Summary: Returns an xs:boolean
indicating whether or not the
value of $arg1
contains (at the beginning, at the end, or
anywhere within) at least one sequence of collation units that provides a
minimal match to the collation units in the value of $arg2
,
according to the collation that is used.
"Minimal match" is defined in
If the value of $arg1
or $arg2
is the empty
sequence, or contains only ignorable collation units, it is interpreted as the zero-length string.
If the value of $arg2
is the zero-length string, then the
function returns true
.
If the value of $arg1
is the zero-length string, the function
returns false
.
The collation used by the invocation of this function is determined according
to the rules in
CollationA used in these examples is a collation in which both "-" and "*" are ignorable collation units.
"Ignorable collation unit" is equivalent to "ignorable collation
element" in
fn:contains ( "tattoo", "t")
returns true
.
fn:contains ( "tattoo", "ttt")
returns false
.
fn:contains ( "", ())
returns true
. The first rule is applied, followed by the second rule.
fn:contains ( "abcdefghi", "-d-e-f-", "CollationA")
returns true
.
fn:contains ( "a*b*c*d*e*f*g*h*i*", "d-ef-",
"CollationA")
returns true
.
fn:contains ( "abcd***e---f*--*ghi", "def",
"CollationA")
returns true
.
fn:contains ( (), "--***-*---", "CollationA")
returns true
. The second argument contains only
ignorable collation units and is equivalent to the zero-length string.
Summary: Returns an xs:boolean
indicating whether or not the
value of $arg1
starts with a sequence of collation units that
provides a minimal match to the collation units of $arg2
according to the collation that is used.
"Minimal match" is defined in
If the value of $arg1
or $arg2
is the empty
sequence, or contains only ignorable collation units, it is interpreted as the zero-length string.
If the value of $arg2
is the zero-length string, then the
function returns true
. If the value of $arg1
is
the zero-length string and the value of $arg2
is not the
zero-length string, then the function returns false
.
The collation used by the invocation of this function is determined according
to the rules in
CollationA used in these examples is a collation in which both "-" and "*" are ignorable collation units.
"Ignorable collation unit" is equivalent to "ignorable collation
element" in
fn:starts-with ( "tattoo", "tat")
returns
true
.
fn:starts-with ( "tattoo", "att")
returns
false
.
fn:starts-with ((), ())
returns true
.
fn:starts-with ( "abcdefghi", "-a-b-c-",
"CollationA")
returns true
.
fn:starts-with ( "a*b*c*d*e*f*g*h*i*", "a-bc-",
"CollationA")
returns true
.
fn:starts-with ( "abcd***e---f*--*ghi", "abcdef",
"CollationA")
returns true
.
fn:starts-with ( (), "--***-*---", "CollationA")
returns true
. The second argument contains only
ignorable collation units and is equivalent to the zero-length string.
Summary: Returns an xs:boolean
indicating whether or not the
value of $arg1
ends with a sequence of collation units that
provides a minimal match to the collation units of $arg2
according to the collation that is used.
"Minimal match" is defined in
If the value of $arg1
or $arg2
is the empty
sequence, or contains only ignorable collation units, it is interpreted as the zero-length string.
If the value of $arg2
is the zero-length string, then the
function returns true
. If the value of $arg1
is
the zero-length string and the value of $arg2
is not the
zero-length string, then the function returns false
.
The collation used by the invocation of this function is determined according
to the rules in
CollationA used in these examples is a collation in which both "-" and "*" are ignorable collation units.
"Ignorable collation unit" is equivalent to "ignorable collation
element" in
fn:ends-with ( "tattoo", "tattoo")
returns
true
.
fn:ends-with ( "tattoo", "atto")
returns
false
.
fn:ends-with ((), ())
returns true
.
fn:ends-with ( "abcdefghi", "-g-h-i-",
"CollationA")
returns true
.
fn:ends-with ( "abcd***e---f*--*ghi", "defghi",
"CollationA")
returns true
.
fn:ends-with ( "abcd***e---f*--*ghi", "defghi",
"CollationA")
returns true
.
fn:ends-with ( (), "--***-*---", "CollationA")
returns true
. The second argument contains only
ignorable collation units and is equivalent to the zero-length string.
Summary: Returns the substring of the value of $arg1
that
precedes in the value of $arg1
the first occurrence of a
sequence of collation units that provides a minimal match to the collation
units of $arg2
according to the collation that is used.
"Minimal match" is defined in
If the value of $arg1
or $arg2
is the empty
sequence, or contains only ignorable collation units, it is interpreted as the zero-length string.
If the value of $arg2
is the zero-length string, then the
function returns the zero-length string.
If the value of $arg1
does not contain a string that is equal to
the value of $arg2
, then the function returns the zero-length
string.
The collation used by the invocation of this function is determined according
to the rules in
CollationA used in these examples is a collation in which both "-" and "*" are ignorable collation units.
"Ignorable collation unit" is equivalent to "ignorable collation
element" in
fn:substring-before ( "tattoo", "attoo")
returns
. t
fn:substring-before ( "tattoo", "tatto")
returns
.
fn:substring-before ((), ())
returns
.
fn:substring-before ( "abcdefghi", "--d-e-",
"CollationA")
returns
. abc
fn:substring-before ( "abc--d-e-fghi", "--d-e-",
"CollationA")
returns
. abc--
fn:substring-before ( "a*b*c*d*e*f*g*h*i*", "***cde",
"CollationA")
returns
. a*b*
fn:substring-before ( "Eureka!", "--***-*---",
"CollationA")
returns . The second argument
contains only ignorable collation units and is equivalent to the
zero-length string.
Summary: Returns the substring of the value of $arg1
that
follows in the value of $arg1
the first occurrence of a
sequence of collation units that provides a minimal match to the collation
units of $arg2
according to the collation that is used.
"Minimal match" is defined in
If the value of $arg1
or $arg2
is the empty
sequence, or contains only ignorable collation units, it is interpreted as the zero-length string.
If the value of $arg2
is the zero-length string, then the
function returns the value of $arg1
.
If the value of $arg1
does not contain a string that is equal to
the value of $arg2
, then the function returns the zero-length
string.
The collation used by the invocation of this function is determined according
to the rules in
CollationA used in these examples is a collation in which both "-" and "*" are ignorable collation units.
"Ignorable collation unit" is equivalent to "ignorable collation
element" in
fn:substring-after ( "tattoo", "tat")
returns
. too
fn:substring-after ( "tattoo", "tattoo")
returns
.
fn:substring-after ((), ())
returns
.
fn:substring-after ( "abcdefghi", "--d-e-",
"CollationA")
returns
.fghi
fn:substring-after ( "abc--d-e-fghi", "--d-e-",
"CollationA")
returns
. -fghi
fn:substring-after ( "a*b*c*d*e*f*g*h*i*", "***cde***",
"CollationA")
returns
. *f*g*h*i*
fn:substring-after ( "Eureka!", "--***-*---",
"CollationA")
returns
. The second argument contains only ignorable collation
units and is equivalent to the zero-length string.Eureka!
The three functions described in this section make use of a regular expression syntax for pattern matching. This is described below.
Function | Meaning |
---|---|
fn:matches
|
Returns an xs:boolean value that indicates whether the
value of the first argument is matched by the regular expression
that is the value of the second argument. |
fn:replace
|
Returns the value of the first argument with every substring matched by the regular expression that is the value of the second argument replaced by the replacement string that is the value of the third argument. |
fn:tokenize
|
Returns a sequence of one or more xs:string s whose
values are substrings of the value of the first argument separated
by substrings that match the regular expression that is the value of
the second argument. |
The regular expression syntax used by these functions is defined in terms of
the regular expression syntax specified in XML Schema (see
It is recommended that implementers consult
The regular expression syntax and semantics are identical to those
defined in
Two meta-characters, ^
and $
are
added. By default, the meta-character ^
matches the
start of the entire string, while $
matches the end
of the entire string. In multi-line mode, ^
matches
the start of any line (that is, the start of the entire string,
and the position immediately after a newline character), while
$
matches the end of any line (that is, the end of
the entire string, and the position immediately before a newline
character). Newline here means the character #x0A
only.
This means that the production in
[10] Char ::= [^.\?*+{}()|#x5B#x5D]
is modified to read:
[10] Char ::= [^.\?*+{}()|^$#x5B#x5D]
The characters #x5B
and #x5D
correspond
to "[
" and "]
" respectively.
The following production:
[11] charClass ::= charClassEsc | charClassExpr | WildCardEsc
is modified to read:
[11] charClass ::= charClassEsc | charClassExpr |
WildCardEsc | "^" | "$"
following a quantifier. Specifically:?
X??
matches X, once or not at all
X*?
matches X, zero or more times
X+?
matches X, one or more times
X{n}?
matches X, exactly n times
X{n,}?
matches X, at least n times
X{n,m}?
matches X, at least n times, but
not more than m times
The effect of these quantifiers is that the regular expression
matches the
, the regular expression matches the
?
To achieve this, the production in
[4] quantifier ::= [?*+] | ( '{' quantity '}' )
is changed to:
[4] quantifier ::= ( [?*+] | ( '{' quantity '}' ) ) '?'?
Reluctant quantifiers have no effect on the results of the
boolean fn:matches
function, since this
function is only interested in discovering whether a match
exists, and not where it exists.
Sub-expressions (groups) within the regular expression are
recognized. The regular expression syntax defined by fn:replace()
function
described below allows access to the parts of the input string
that matched a sub-expression (called captured substrings). The
sub-expressions are numbered according to the position of the
opening parenthesis in left-to-right order within the top-level
regular expression: the first opening parenthesis identifies
captured substring 1, the second identifies captured substring
2, and so on. 0 identifies the substring captured by the entire
regular expression. If a sub-expression matches more than one
substring (because it is within a construct that allows
repetition), then only the
Back-references are allowed. The construct \n
where
n
is a single digit is always recognized as a
back-reference; if this is followed by further digits, these
digits are taken to be part of the back-reference if and only if
the back-reference is preceded by sufficiently many capturing
subexpressions. A back-reference matches the string that was
matched by the n'th capturing subexpression within the regular
expression, that is, the parenthesized subexpression whose
opening left parenthesis is the n
'th unescaped left
parenthesis within the regular expression. The closing right
parenthesis of this subexpression must occur before the
back-reference. For example, the regular expression
('|").*\1
matches a sequence of characters
delimited either by an apostrophe at the start and end, or by a
quotation mark at the start and end.
Back references change the following production:
[23] charClassEsc ::= ( SingleCharEsc | MultiCharEsc |
catEsc | complEsc )
to
[23] charClassEsc ::= ( SingleCharEsc | MultiCharEsc |
catEsc | complEsc | backReference )
[23a] backReference ::= "\" [1-9][0-9]*
Single character escapes are extended to allow the
$
character to be escaped. The following production
is changed:
[24]SingleCharEsc ::= '\' [nrt\|.?*+(){}#x2D#x5B#x5D#x5E]
to
[24]SingleCharEsc ::= '\' [nrt\|.?*+(){}$#x2D#x5B#x5D#x5E]
All these functions provide an optional parameter, $flags
,
to set options for the interpretation of the regular expression. The
parameter accepts a xs:string
, in which individual letters
are used to set options. The presence of a letter within the string
indicates that the option is on; its absence indicates that the option
is off. Letters may appear in any order and may be repeated. If there
are characters present that are not defined here as flags, then an error
is raised
The following options are defined:
s
: If present, the match operates in "dot-all"
mode. (Perl calls this the single-line mode.) If the
s
flag is not specified, the meta-character
.
matches any character except a newline
(#x0A
) character. In dot-all mode, the
meta-character .
matches any character whatsoever.
Suppose the input contains "hello" and "world" on two lines.
This will not be matched by the regular expression
"hello.*world" unless dot-all mode is enabled.
m
: If present, the match operates in multi-line
mode. By default, the meta-character ^
matches the
start of the entire string, while $ matches the end of the
entire string. In multi-line mode, ^
matches the
start of any line (that is, the start of the entire string, and
the position immediately after a newline character), while
$
matches the end of any line (that is, the end of
the entire string, and the position immediately before a newline
character). Newline here means the character #x0A
only.
i
: If present, the match operates in
case-insensitive mode. Otherwise, the match operates in
case-sensitive mode. In case-sensitive mode, a character in the
input string matches a character specified by the pattern only
if the Unicode code points match. In case-insensitive mode, a
character in the input string matches a character specified by
the pattern if there is a default case mapping between the two
characters as defined in section 3.13 of
x
: If present, whitespace characters within the
regular expression are ignored. By default, whitespace
characters match themselves. This allows, for example, regular
expressions to be broken up into lines for readability.
Summary: The function returns true
if $input
matches the regular expression supplied as $pattern
as
influenced by the value of $flags
, if present; otherwise, it
returns false
.
The effect of calling the first version of this function (omitting the
argument $flags
) is the same as the effect of calling the
second version with the $flags
argument set to a zero-length
string. Flags are defined in
If $input
is the empty sequence, it is interpreted as the
zero-length string.
Unless the metacharacters ^
and $
are used as
anchors, the string is considered to match the pattern if any substring
matches the pattern. But if anchors are used, the anchors must match the
start/end of the string (in string mode), or the start/end of a line (in
multiline mode).
This is different from the behavior of patterns in
An error is raised $pattern
is invalid according to the rules described in section
An error is raised $flags
is invalid according to the rules described in section
fn:matches("abracadabra", "bra")
returns true
fn:matches("abracadabra", "^a.*a$")
returns true
fn:matches("abracadabra", "^bra")
returns false
Given the source document:
the following function calls produce the following results, with the
poem
element as the context node:
fn:matches(., "Kaum.*krähen")
returns false
fn:matches(., "Kaum.*krähen", "s")
returns true
fn:matches(., "^Kaum.*gesehen,$", "m")
returns true
fn:matches(., "^Kaum.*gesehen,$")
returns false
fn:matches(., "kiki", "i")
returns true
Regular expression matching is defined on the basis of Unicode code points; it takes no account of collations.
Summary: The function returns the xs:string
that is obtained by
replacing each non-overlapping substring of $input
that matches
the given $pattern
with an occurrence of the
$replacement
string.
The effect of calling the first version of this function (omitting the
argument $flags
) is the same as the effect of calling the
second version with the $flags
argument set to a zero-length
string. Flags are defined in
The $flags
argument is interpreted in the same manner as for the
fn:matches()
function.
If $input
is the empty sequence, it is interpreted as the
zero-length string.
If two overlapping substrings of $input
both match the
$pattern
, then only the first one (that is, the one whose first
character comes first in the $input
string) is replaced.
Within the $replacement
string, a variable $N
may be used to refer to the substring captured by the Nth parenthesized sub-expression in the regular expression. For each match of the pattern, these variables are assigned the value of the content matched by the relevant sub-expression, and the modified replacement string is then substituted for the characters in $input
that matched the pattern. $0
refers to the substring captured by the regular expression as a whole.
More specifically, the rules are as follows, where S
is the number of parenthesized sub-expressions in the regular expression, and N
is the decimal number formed by taking all the digits that consecutively follow the $
character:
If
If
If
Otherwise (if N
=0
, then the variable is replaced by the substring matched by the regular expression as a whole.1
<=N
<=S
, then the variable is replaced by the substring captured by the Nth parenthesized sub-expression. If the Nth
parenthesized sub-expression was not matched, then the variable is replaced by the zero-length string.
S
<N
<=9
, then the variable is replaced by the zero-length string.
N
>S
and N
>9
), the last digit of N
is taken to be a literal character to be included "as is" in the replacement string, and the rules are reapplied using the number N
formed by stripping off this last digit.
For example, if the replacement string is
and there are 5 substrings, the result contains the value of the substring that matches the second sub-expression, followed by the digit $23
.3
A literal
symbol must be written as $
.\$
A literal
symbol must be written as \
.\\
If two alternatives within the pattern both match at the same position in
the $input
, then the match that is chosen is the one matched by
the first alternative. For example:
An error is raised $pattern
is invalid according to the rules described in section
An error is raised $flags
is invalid according to the rules described in section
An error is raised fn:matches("",
$pattern, $flags)
returns true
. It is not an error,
however, if a captured substring is zero-length.
An error is raised $replacement
contains a "$
" character that is not
immediately followed by a digit 0-9
and not immediately
preceded by a "\".
An error is raised $replacement
contains a "\
" character that is not
part of a "\\
" pair, unless it is immediately followed by a
"$
" character.
replace("abracadabra", "bra", "*")
returns "a*cada*"
replace("abracadabra", "a.*a", "*")
returns "*"
replace("abracadabra", "a.*?a", "*")
returns "*c*bra"
replace("abracadabra", "a", "")
returns "brcdbr"
replace("abracadabra", "a(.)", "a$1$1")
returns "abbraccaddabbra"
replace("abracadabra", ".*?", "$1")
raises an
error, because the pattern matches the zero-length string
replace("AAAA", "A+", "b")
returns
b
replace("AAAA", "A+?", "b")
returns
bbbb
replace("darted", "^(.*?)d(.*)$", "$1c$2")
returns
. The first carted
is replaced.d
Summary: This function breaks the $input
string into a sequence
of strings, treating any substring that matches $pattern
as a
separator. The separators themselves are not returned.
The effect of calling the first version of this function (omitting the
argument $flags
) is the same as the effect of calling the
second version with the $flags
argument set to a zero-length
string. Flags are defined in
The $flags
argument is interpreted in the same way as for the
fn:matches()
function.
If $input
is the empty sequence, or if $input
is the zero-length string, the result is the empty sequence.
If the supplied $pattern
matches a zero-length string, that is,
if fn:matches("", $pattern, $flags)
returns true
,
then an error is raised:
If a separator occurs at the start of the $input
string, the
result sequence will start with a zero-length string. Zero-length strings
will also occur in the result sequence if a separator occurs at the end of
the $input
string, or if two adjacent substrings match the
supplied $pattern
.
If two alternatives within the supplied $pattern
both match at
the same position in the $input
string, then the match that is
chosen is the first. For example:
An error is raised $pattern
is invalid according to the rules described in section
An error is raised $flags
is invalid according to the rules described in section
fn:tokenize("The cat sat on the mat", "\s+")
returns ("The", "cat", "sat", "on", "the", "mat")
fn:tokenize("1, 15, 24, 50", ",\s*")
returns
("1", "15", "24", "50")
fn:tokenize("1,15,,24,50,", ",")
returns
("1", "15", "", "24", "50", "")
fn:tokenize("abba", ".?")
raises the error
fn:tokenize("Some unparsed <br> HTML
<BR> text", "\s*<br>\s*", "i")
returns ("Some unparsed", "HTML", "text")
This section specifies functions that take anyURI as arguments.
Function | Meaning |
---|---|
fn:resolve-uri
|
Returns an xs:anyURI representing an absolute
xs:anyURI given a base URI and a relative URI. |
Summary: The second form of this function expects $base
to be an absolute URI
and $relative
to be an absolute or a relative URI reference. If $relative
is a relative URI
reference, it is resolved against $base
, using an algorithm such as the ones described in $relative
is an
absolute URI reference, it is returned unchanged. The first form of
this function resolves $relative
against the value of the base-uri property from the
static context. If the base-uri property is not initialized in the static
context an error is raised
If $relative
or $base
is not a valid
xs:anyURI
an error is raised
If $relative
is the empty sequence, the empty sequence is returned.
If $relative
is the zero-length string, returns the value of the
base-uri property from the static context in the first form (if the base-uri
property is not initialized in the static context an error is raised
$base
in the second form.
Resolving a URI does not dereference it. This is merely a syntactic operation on two character strings.
This section defines functions and operators on the
The following additional constructor functions are defined on the boolean type.
Function | Meaning |
---|---|
fn:true
|
Constructs the xs:boolean value 'true'. |
fn:false
|
Constructs the xs:boolean value 'false'. |
Summary: Returns the xs:boolean
value true
.
Equivalent to xs:boolean("1")
.
fn:true()
returns true
.
Summary: Returns the xs:boolean
value false
.
Equivalent to xs:boolean("0")
.
fn:false()
returns false
.
The following functions define the semantics of operators on boolean values in
Operator | Meaning |
---|---|
op:boolean-equal
|
Equality of xs:boolean values |
op:boolean-less-than
|
A less-than operator on xs:boolean values:
false is less than true . |
op:boolean-greater-than
|
A greater-than operator on xs:boolean values:
true is greater than false . |
The ordering operators op:boolean-less-than
and op:boolean-greater-than
are provided for application purposes
and for compatibility with xs:boolean
is not ordered.
Summary: Returns true
if both arguments are true
or
if both arguments are false
. Returns false
if one
of the arguments is true
and the other argument is
false
.
This function backs up the "eq" operator on xs:boolean
values.
Summary: Returns true
if $arg1
is
false
and $arg2
is true
. Otherwise,
returns false
.
This function backs up the "lt" and "ge" operators on xs:boolean
values.
Summary: Returns true
if $arg1
is true
and $arg2
is false
. Otherwise, returns false
.
This function backs up the "gt" and "le" operators on xs:boolean
values.
The following functions are defined on boolean values:
Function | Meaning |
---|---|
fn:not
|
Inverts the xs:boolean value of the argument. |
Summary: $arg
is first reduced to an effective boolean value by
applying the fn:boolean()
function. Returns true
if the effective boolean value is false
, and false
if the effective boolean value is true
.
fn:not(fn:true())
returns false
.
fn:not("false")
returns false
.
This section discusses operations on the xs:duration
that are
defined in this document. See
The operators described in this section are defined on the following date and time types:
xs:dateTime
xs:date
xs:time
xs:gYearMonth
xs:gYear
xs:gMonthDay
xs:gMonth
xs:gDay
Note that only equality is defined on
xs:gYearMonth
, xs:gYear
,
xs:gMonthDay
, xs:gMonth
and xs:gDay
values.
In addition, operators are defined on:
xs:duration
and on the
xdt:yearMonthDuration
xdt:dayTimeDuration
Note that only equality is defined on
xs:duration
values.
For a number of the above datatypes
All
A processor that limits the number of digits in date and time datatype
representations may encounter overflow and underflow conditions when it
tries to execute the functions in
The value spaces of the two totally ordered subtypes of
xs:duration
described in xs:integer
months for xdt:yearMonthDuration
and xs:decimal
seconds for xdt:dayTimeDuration
. If
a processor limits the number of digits allowed in the representation of
xs:integer
and xs:decimal
then overflow and
underflow situations can arise when it tries to execute the functions in
As defined in xs:dateTime
, xs:date
, xs:time
, xs:gYearMonth
, xs:gYear
, xs:gMonthDay
, xs:gMonth
, xs:gDay
values, referred to collectively as date/time values, are represented as seven components or properties: year
, month
, day
, hour
, minute
, second
and timezone
. The value of the first five components are xs:integer
s. The value of the second
component is an xs:decimal
and the value of the timezone
component is an xdt:dayTimeDuration
. For all the date/time datatypes, the timezone
property is optional and may or may not be present. Depending on the datatype, some of the remaining six properties must be present and some must be absent. Absent, or missing, properties are represented by the empty sequence. This value is referred to as the xs:dateTime
values, this local value
For xs:time
, "00:00:00"
and "24:00:00"
are alternate lexical forms for the same value. For xs:dateTime
,
a time component "24:00:00"
translates to "00:00:00"
of the following day.
An xs:dateTime
with lexical
representation 1999-05-31T05:00:00
is represented in the datamodel by {1999, 5, 31, 5, 0, 0.0, ()}
.
An xs:dateTime
with lexical
representation 1999-05-31T13:20:00-05:00
is represented by {1999, 5, 31, 13, 20, 0.0, -PT5H}
.
An xs:dateTime
with lexical
representation 1999-12-31T24:00:00
is represented by {2000, 1, 1, 0, 0, 0.0, ()}
.
An xs:date
with lexical
representation 2005-02-28+8:00
is represented by {2005, 2, 28, (), (), (), PT8H}
.
An xs:time
with lexical
representation 24:00:00
is represented by {(), (), (), 0, 0, 0, ()}
.
Two totally ordered subtypes of xs:duration
are defined in http://www.w3.org/2005/xpath-datatypes
.
The XML Schema for these two derived datatypes is shown in
[Definition] xdt:yearMonthDuration
is derived from
xs:duration
by restricting its lexical representation to
contain only the year and month components. The value space of
xdt:yearMonthDuration
is the set of xs:integer
month values. The year and month components of
xdt:yearMonthDuration
correspond to the Gregorian year and
month components defined in section 5.5.3.2 of
The lexical representation for xdt:yearMonthDuration
is the
xs:integer
.
An optional preceding minus sign ('-') is allowed to indicate a negative
duration. If the sign is omitted a positive duration is indicated. To
indicate a xdt:yearMonthDuration
of 1 year, 2 months, one
would write: P1Y2M. One could also indicate a
xdt:yearMonthDuration
of minus 13 months as: -P13M.
Reduced precision and truncated representations of this format are allowed provided they conform to the following:
If the number of years or months in any expression equals zero (0), the
number and its corresponding designator
The value of a xdt:yearMonthDuration
lexical form is
obtained by multiplying the value of the years component by 12 and
adding the value of the months component. The value is positive or
negative depending on the preceding sign.
The canonical representation of xdt:yearMonthDuration
restricts the value of the months component to xs:integer
values between 0 and 11, both inclusive. To convert from a non-canonical
representation to the canonical representation, the lexical
representation is first converted to a value in xs:integer
months as defined above. This value is then divided by 12 to obtain the
value of the years component of the canonical representation. The
remaining number of months is the value of the months component of the
canonical representation. For negative durations, the canonical form is
calculated using the absolute value of the duration and a negative sign
is prepended to it. If a component has the value zero (0), then the
number and the designator for that component
Let the function that calculates the value of an
xdt:yearMonthDuration
in the manner described above be
called V(d). Then for two xdt:yearMonthDuration
values x
and y, x > y if and only if V(x) > V(y). The order relation on
yearMonthDuration
is a total order.
[Definition] xdt:dayTimeDuration
is derived from
xs:duration
by restricting its lexical representation to
contain only the days, hours, minutes and seconds components. The value
space of xdt:dayTimeDuration
is the set of fractional second
values. The components of xdt:dayTimeDuration
correspond to the
day, hour, minute and second components defined in Section 5.5.3.2 of
The lexical representation for xdt:dayTimeDuration
is the
The values of the days, hours and minutes components are not restricted,
but allow an arbitrary unsigned xs:integer
. Similarly, the
value of the seconds component allows an arbitrary unsigned
xs:decimal
. An optional minus sign ('-') is allowed to
precede the 'P', indicating a negative duration. If the sign is omitted,
the duration is positive. See also
For example, to indicate a duration of 3 days, 10 hours and 30 minutes, one would write: P3DT10H30M. One could also indicate a duration of minus 120 days as: -P120D. Reduced precision and truncated representations of this format are allowed, provided they conform to the following:
If the number of days, hours, minutes, or seconds in any
expression equals zero (0), the number and its corresponding
designator
The seconds part
The designator 'T'
For example, P13D, PT47H, P3DT2H, -PT35.89S and P4D251M are all allowed. P-134D is not allowed (invalid location of minus sign), although -P134D is allowed.
The value of a xdt:dayTimeDuration
lexical form in
fractional seconds is obtained by converting the days, hours, minutes
and seconds value to fractional seconds using the conversion rules: 24
hours = 1 day, 60 minutes = 1 hour and 60 seconds = 1 minute.
The canonical representation of xdt:dayTimeDuration
restricts the value of the hours component to xs:integer
values between 0 and 23, both inclusive; the value of the minutes
component to xs:integer
values between 0 and 59; both
inclusive; and the value of the seconds component to
xs:decimal
valued from 0.0 to 59.999... (see
To convert from a non-canonical representation to the canonical
representation, the value of the lexical form in fractional seconds is
first calculated in the manner described above. The value of the days
component in the canonical form is then calculated by dividing the value
by 86,400 (24*60*60). The remainder is in fractional seconds. The value
of the hours component in the canonical form is calculated by dividing
this remainder by 3,600 (60*60). The remainder is again in fractional
seconds. The value of the minutes component in the canonical form is
calculated by dividing this remainder by 60. The remainder in fractional
seconds is the value of the seconds component in the canonical form. For
negative durations, the canonical form is calculated using the absolute
value of the duration and a negative sign is prepended to it. If a
component has the value zero (0) then the number and the designator for
that component must be omitted. However, if all the components of the
lexical form are zero (0), the canonical form is PT0S
.
Let the function that calculates the value of a
xdt:dayTimeDuration
in the manner described above be called
xdt:dayTimeDuration
values
xdt:dayTimeDuration
is a total order.
Operator | Meaning |
---|---|
op:yearMonthDuration-equal
|
Equality comparison on xdt:yearMonthDuration values |
op:yearMonthDuration-less-than
|
Less-than comparison on xdt:yearMonthDuration values |
op:yearMonthDuration-greater-than
|
Greater-than comparison on xdt:yearMonthDuration values |
op:dayTimeDuration-equal
|
Equality comparison on xdt:dayTimeDuration values |
op:dayTimeDuration-less-than
|
Less-than comparison on xdt:dayTimeDuration values |
op:dayTimeDuration-greater-than
|
Greater-than comparison on xdt:dayTimeDuration values |
op:duration-equal
|
Equality comparison on xs:duration values |
op:dateTime-equal
|
Equality comparison on xs:dateTime values |
op:dateTime-less-than
|
Less-than comparison on xs:dateTime values |
op:dateTime-greater-than
|
Greater-than comparison on xs:dateTime values |
op:date-equal
|
Equality comparison on xs:date values |
op:date-less-than
|
Less-than comparison on xs:date values |
op:date-greater-than
|
Greater-than comparison on xs:date values |
op:time-equal
|
Equality comparison on xs:time values |
op:time-less-than
|
Less-than comparison on xs:time values |
op:time-greater-than
|
Greater-than comparison on xs:time values |
op:gYearMonth-equal
|
Equality comparison on xs:gYearMonth values |
op:gYear-equal
|
Equality comparison on xs:gYear values |
op:gMonthDay-equal
|
Equality comparison on xs:gMonthDay values |
op:gMonth-equal
|
Equality comparison on xs:gMonth values |
op:gDay-equal
|
Equality comparison on xs:gDay values |
The following comparison operators are defined on the xs:boolean
result. As discussed in xs:duration
is
not a total order but, rather, a partial order. For this reason, only equality is defined on xs:duration
. A full complement of comparison and
arithmetic functions are defined on the two subtypes of duration described in
An xs:dateTime
can be considered to consist of seven components:
year
, month
, day
, hour
, minute
, second
and timezone
. For xs:dateTime
six components: year
, month
, day
, hour
, minute
and second
are required and timezone
is optional. For other date/time values, of the first six components, some are required and others must be absent or missing. Timezone
is always optional. For example, for xs:date
, the year
, month
and day
components are required and hour
, minute
and second
components must be absent; for xs:time
the hour
, minute
and second
components are required and year
, month
and day
are missing; for xs:gDay
, day
is required and year
, month
, hour
, minute
and second
are missing.
Values of the date/time datatypes xs:time
, xs:gMonthDay
, xs:gMonth
, and xs:gDay
, can be considered to represent a sequence of recurring time instants or time periods. An xs:time
occurs every day. An xs:gMonth
occurs every year. Comparison operators on these datatypes compare the starting instants of equivalent occurrences in the recurring series. These xs:dateTime
values are calculated as described below.
Comparison operators on xs:date
, xs:gYearMonth
and xs:gYear
compare their starting instants. These xs:dateTime
values are calculated as described below.
The starting instant of an occurrence of a date/time value is an xs:dateTime
calculated by filling in the missing components of the local value from a reference xs:dateTime
. If the value filled in for a missing day component exceeds the maximum day value for the month, the last day of the month is used. Suppose, for example, that the reference xs:dateTime
is 1972-12-31T00:00:00
and the xs:date
value to be compared is 1993-03-31
. Filling in the time components from the reference xs:dateTime
we get 1993-03-31T00:00:00
which is the starting instant of that day. Similarly, if the xs:time
value 12:30:00
is to be compared, we fill in the missing components from the reference xs:dateTime
and we get 1972-12-31T12:30:00
which is the time on that day. For an xs:gYearMonth
value of 1976-02
we fill in the missing components, adjust for the last day in the month and get 1976-02-29T00:00:00
.
If the xs:time
value written as
24:00:00
is to be compared, filling in the missing components gives 1972-12-31T00:00:00
, because 24:00:00
is an alternative representation of 00:00:00
(the lexical value "24:00:00"
is
converted to the time components {0,0,0} before the missing components are filled
in). This has the consequence that when ordering xs:time
values,
24:00:00
is
considered to be earlier than 23:59:59
. However, when ordering
xs:dateTime
values, a time component of 24:00:00
is considered equivalent to 00:00:00
on the
following day.
Note that the reference xs:dateTime
does not have a timezone. The timezone
component is never filled in from the reference xs:dateTime
. In some cases, if the date/time value does not have a timezone, the implicit timezone from the dynamic context is used as the timezone.
This proposal uses the reference xs:dateTime 1972-12-31T00:00:00
in the description of the comparison operators. Implementations are allowed to use other reference xs:dateTime
values as long as they yield the same results. The reference xs:dateTime
used must meet the following constraints: when it is used to supply components into xs:gMonthDay
values, the year must allow for February 29 and so must be a leap year; when it is used to supply missing components into xs:gDay
values, the month must allow for 31 days. Different reference xs:dateTime
values may be used for different operators.
Summary: Returns true
if and only if $arg1
is equal
to $arg2
. Returns false
otherwise.
This function backs up the "eq", "ne", "le" and "ge" operators on
xdt:yearMonthDuration
values.
Summary: Returns true
if and only if $arg1
is less
than $arg2
. Returns false
otherwise.
This function backs up the "lt" and "le" operators on
xdt:yearMonthDuration
values.
Summary: Returns true
if and only if $arg1
is
greater than $arg2
. Returns false
otherwise.
This function backs up the "gt" and "ge" operators on
xdt:yearMonthDuration
values.
Summary: Returns true
if and only if the value of
$arg1
is equal to the value of $arg2
. Returns
false
otherwise.
This function backs up the "eq", "ne", "le" and "ge" operators on
xdt:dayTimeDuration
values.
Summary: Returns true
if and only if $arg1
is less
than $arg2
. Returns false
otherwise.
This function backs up the "lt" and "le" operators on
xdt:dayTimeDuration
values.
Summary: Returns true
if and only if $arg1
is
greater than $arg2
. Returns false
otherwise.
This function backs up the "gt" and "ge" operators on
xdt:dayTimeDuration
values.
Summary:
Returns true
if and only if the
xdt:yearMonthDuration
and the xdt:dayTimeDuration
components of $arg1
and $arg2
compare equal respectively.
Returns false
otherwise.
This function backs up the "eq" and "ne" operators on
xs:duration
values.
The semantics of this function are:
op:duration-equal(xs:duration("P1Y"), xs:duration("P12M"))
returns true
.
op:duration-equal(xs:duration("PT24H"), xs:duration("P1D"))
returns true
.
op:duration-equal(xs:duration("P1Y"), xs:duration("P365D"))
returns false
.
Summary:
Returns true
if and only if the value of
$arg1
is equal to the value of $arg2
according to the algorithm defined in section 3.2.7.4 of Order relation on dateTime
for xs:dateTime
values with timezones.
Returns false
otherwise.
This function backs up the "eq", "ne", "le" and "ge" operators on
xs:dateTime
values.
Assume that the dynamic context provides an implicit timezone value of -05:00
.
op:dateTime-equal(xs:dateTime("2002-04-02T12:00:00-01:00"),
xs:dateTime("2002-04-02T17:00:00+04:00"))
returns true
.
op:dateTime-equal(xs:dateTime("2002-04-02T12:00:00"),
xs:dateTime("2002-04-02T23:00:00+06:00"))
returns true
.
op:dateTime-equal(xs:dateTime("2002-04-02T12:00:00"),
xs:dateTime("2002-04-02T17:00:00"))
returns false
.
op:dateTime-equal(xs:dateTime("2002-04-02T12:00:00"),
xs:dateTime("2002-04-02T12:00:00"))
returns true
.
op:dateTime-equal(xs:dateTime("2002-04-02T23:00:00-04:00"),
xs:dateTime("2002-04-03T02:00:00-01:00"))
returns true
.
op:dateTime-equal(xs:dateTime("1999-12-31T24:00:00"),
xs:dateTime("2000-01-01T00:00:00"))
returns true
.
op:dateTime-equal(xs:dateTime("2005-04-04T24:00:00"),
xs:dateTime("2005-04-04T00:00:00"))
returns false
.
Summary: Returns true
if and only if the value of
$arg1
is less than the value of $arg2
according to the algorithm defined in section 3.2.7.4 of Order relation on dateTime
for xs:dateTime
values with timezones.
Returns false
otherwise.
This function backs up the "lt" and "le" operators on
xs:dateTime
values.
Summary: Returns true
if and only if the value of
$arg1
is greater than the value of $arg2
according to the algorithm defined in section 3.2.7.4 of Order relation on dateTime
for xs:dateTime
values with timezones.
Returns false
otherwise.
This function backs up the "gt" and "ge" operators on
xs:dateTime
values.
Summary: Returns true
if and only if the starting instant of
$arg1
is equal to starting instant of $arg2
.
Returns false
otherwise.
The starting instant of an xs:date
is the xs:dateTime
at time 00:00:00
on that date.
The two starting instants are compared using op:dateTime-equal
.
This function backs up the "eq", "ne", "le" and "ge" operators on xs:date
values.
op:date-equal(xs:date("2004-12-25Z"),
xs:date("2004-12-25+07:00"))
returns false
. The starting instants are xs:dateTime("2004-12-25T00:00:00Z")
and xs:dateTime("2004-12-25T00:00:00+07:00")
. These are normalized to xs:dateTime("2004-12-25T00:00:00Z")
and xs:dateTime("2004-12-24T17:00:00Z")
.
op:date-equal(xs:date("2004-12-25-12:00"),
xs:date("2004-12-26+12:00"))
returns true
.
Summary: Returns true
if and only if the starting instant of
$arg1
is less than the starting instant of $arg2
.
Returns false
otherwise.
The starting instant of an xs:date
is the xs:dateTime
at time 00:00:00
on that date.
The two starting instants are compared using op:dateTime-less-than
.
This function backs up the "lt" and "le" operators on xs:date
values.
op:date-less-than(xs:date("2004-12-25Z"),
xs:date("2004-12-25-05:00"))
returns true
.
op:date-less-than(xs:date("2004-12-25-12:00"),
xs:date("2004-12-26+12:00"))
returns false
.
Summary: Returns true
if and only if the starting instant of
$arg1
is greater than the starting instant of $arg2
. Returns false
otherwise.
The starting instant of an xs:date
is the xs:dateTime
at time 00:00:00
on that date.
The two starting instants are compared using op:dateTime-greater-than
.
This function backs up the "gt" and "ge" operators on xs:date
values.
op:date-greater-than(xs:date("2004-12-25Z"),
xs:date("2004-12-25+07:00"))
returns true
.
op:date-greater-than(xs:date("2004-12-25-12:00"),
xs:date("2004-12-26+12:00"))
returns false
.
Summary: Returns true
if and only if the value of
$arg1
converted to an xs:dateTime
using the date components from the reference xs:dateTime
is equal to the value of $arg2
converted to an xs:dateTime
using the date components from the same reference xs:dateTime
.
Returns false
otherwise.
The two xs:dateTime
values are compared using op:dateTime-equal
.
This function backs up the "eq", "ne", "le" and "ge" operators on xs:time
values.
Assume that the date components from the reference xs:dateTime
correspond to 1972-12-31
.
op:time-equal(xs:time("08:00:00+09:00"),
xs:time("17:00:00-06:00"))
returns false
. The xs:dateTime>
s calculated using the reference date components are 1972-12-31T08:00:00+09:00
and 1972-12-31T17:00:00-06:00
.
These normalize to 1972-12-30T23:00:00Z
and 1972-12-31T23:00:00
.
op:time-equal(xs:time("21:30:00+10:30"),
xs:time("06:00:00-05:00"))
returns true
.
op:time-equal(xs:time("24:00:00+01:00"), xs:time("00:00:00+01:00"))
returns true
.
Summary: Returns true
if and only if the value of
$arg1
converted to an xs:dateTime
using the date components from the reference xs:dateTime
is less than the normalized value of $arg2
converted to an xs:dateTime
using the date components from the same reference xs:dateTime
.
Returns false
otherwise.
The two xs:dateTime
values are compared using op:dateTime-less-than
.
This function backs up the "lt" and "le" operators on xs:time
values.
Assume that the dynamic context provides an implicit timezone value of -05:00
.
op:time-less-than(xs:time("12:00:00"),
xs:time("23:00:00+06:00"))
returns false
.
op:time-less-than(xs:time("11:00:00"),
xs:time("17:00:00Z"))
returns true
.
op:time-less-than(xs:time("23:59:59"), xs:time("24:00:00"))
returns false
.
Summary: Returns true
if and only if the value of
$arg1
converted to an xs:dateTime
using the date components from the reference xs:dateTime
is greater than the value of
$arg2
converted to an xs:dateTime
using the date components from the same reference xs:dateTime
. Returns false
otherwise.
The two xs:dateTime
values are compared using op:dateTime-greater-than
.
This function backs up the "gt" and "ge" operators on xs:time
values.
op:time-greater-than(xs:time("08:00:00+09:00"),
xs:time("17:00:00-06:00"))
returns false
.
Summary: Returns true
if and only if the xs:dateTime
s representing the starting instants of $arg1
and $arg2
compare equal. The starting instants of $arg1
and $arg2
are calculated by adding the missing components of $arg1
and $arg2
from the xs:dateTime
template xxxx-xx-ddT00:00:00
where dd
represents the last day of the month
component in $arg1
or $arg2
. Returns false
otherwise.
The two xs:dateTime
values representing the starting instants of $arg1
and $arg2
are compared using op:dateTime-equal
.
This function backs up the "eq" and "ne" operators on
xs:gYearMonth
values.
Assume that the dynamic context provides an implicit timezone value of -05:00
.
op:gYearMonth-equal(xs:gYearMonth("1976-02"),
xs:gYearMonth("1976-03Z"))
returns false
. The starting instants are 1972-02-29T00:00:00-05:00
and 1972-03-31T00:00:00Z
, respectively.
op:gYearMonth-equal(xs:gYearMonth("1976-03"),
xs:gYearMonth("1976-03Z"))
returns false
.
Summary: Returns true
if and only if the xs:dateTime
s representing the starting instants of $arg1
and $arg2
compare equal. The starting instants of $arg1
and $arg2
are calculated by adding the missing components of $arg1
and $arg2
from a xs:dateTime
template such as xxxx-01-01T00:00:00
. Returns false
otherwise.
The two xs:dateTime
values representing the starting instants of $arg1
and $arg2
are compared using op:dateTime-equal
.
This function backs up the "eq" and "ne" operators on xs:gYear
values.
Assume that the dynamic context provides an implicit timezone value of -05:00
. Assume, also, that the xs:dateTime
template is xxxx-01-01T00:00:00
.
op:gYear-equal(xs:gYear("2005-12:00"),
xs:gYear("2005+12:00"))
returns false
. The starting instants are 2005-01-01T00:00:00-12:00
and 2005-01-01T00:00:00+12:00
, respectively, and normalize to 2005-01-015T12:00:00Z
and 2004-12-31T12:00:00Z
.
op:gYear-equal(xs:gYear("1976-05:00"),
xs:gYear("1976"))
returns true
.
Summary: Summary: Returns true
if and only if the xs:dateTime
s representing the starting instants of equivalent occurrences of $arg1
and $arg2
compare equal. The starting instants of equivalent occurrences of $arg1
and $arg2
are calculated by adding the missing components of $arg1
and $arg2
from an xs:dateTime
template such as 1972-xx-xxT00:00:00
. Returns false
otherwise.
The two xs:dateTime
values representing the starting instants of equivalent occurrences of $arg1
and $arg2
are compared using op:dateTime-equal
.
This function backs up the "eq" and "ne" operators on
xs:gMonthDay
values.
Assume that the dynamic context provides an implicit timezone value of -05:00
. Assume, also, that the xs:dateTime
template is 1976-xx-xxT00:00:00
.
op:gMonthDay-equal(xs:gMonthDay("--12-25-14:00"),
xs:gMonthDay("--12-26+10:00"))
returns true
. The starting instants are 1976-12-25T00:00:00-14:00
and 1976-12-26T00:00:00+10:00
, respectively, and normalize to 1976-12-25T14:00:00Z
and 1976-12-25T14:00:00Z
.
op:gMonthDay-equal(xs:gMonthDay("--12-25"),
xs:gMonthDay("--12-26Z"))
returns false
.
Summary: Returns true
if and only if the xs:dateTime
s representing the starting instants of equivalent occurrences of $arg1
and $arg2
compare equal. The starting instants of equivalent occurrences of $arg1
and $arg2
are calculated by adding the missing components of $arg1
and $arg2
from an xs:dateTime
template such as 1972-xx-ddT00:00:00
where dd
represents the last day of the month component in $arg1
or $arg2
. Returns false
otherwise.
The two xs:dateTime
values representing the starting instants of equivalent occurrences of $arg1
and $arg2
are compared using op:dateTime-equal
.
This function backs up the "eq" and "ne" operators on xs:gMonth
values.
Assume that the dynamic context provides an implicit timezone value of -05:00
. Assume, also, that the xs:dateTime
template is 1972-xx-ddT00:00:00
.
op:gMonth-equal(xs:gMonth("--12--14:00"),
xs:gMonth("--12-+10:00")
returns false
. The starting instants are 1972-12-31T00:00:00-14:00
and 1972-12-31T00:00:00+10:00
, respectively, and normalize to 1972-01-01T14:00:00Z
and 1972-12-30T14:00:00Z
.
op:gMonth-equal(xs:gMonth("--12-"), "),
xs:gMonth("--12-Z"))
returns false
.
Summary: Returns true
if and only if the xs:dateTime
s representing the starting instants of equivalent occurrences of $arg1
and $arg2
compare equal. The starting instants of equivalent occurrences of $arg1
and $arg2
are calculated by adding the missing components of $arg1
and $arg2
from an xs:dateTime
template such as 1972-12-xxT00:00:00
. Returns false
otherwise.
The two xs:dateTime
values representing the starting instants of equivalent occurrences of $arg1
and $arg2
are compared using op:dateTime-equal
.
This function backs up the "eq" and "ne" operators on xs:gDay
values.
Assume that the dynamic context provides an implicit timezone value of -05:00
. Assume, also, that the xs:dateTime
template is 1976-xx-xxT00:00:00
.
op:gDay-equal(xs:gDay("---25-14:00"),
xs:gDay("---25+10:00"))
returns false
. The starting instants are 1972-12-25T00:00:00-14:00
and 1972-12-25T00:00:00+10:00
, respectively, and normalize to 1972-12-25T14:00:00Z
and 1972-12-24T14:00:00Z
.
op:gDay-equal(xs:gDay("---12"),
xs:gDay("---12Z"))
returns false
.
The duration, date and time datatypes may be considered to be composite datatypes in that they contain distinct properties or components. The extraction functions specified below extract a single component from a duration, date or time value. For the date/time datatypes the local value is used.
Function | Meaning |
---|---|
fn:years-from-duration
|
Returns the year component of an xdt:yearMonthDuration
value. |
fn:months-from-duration
|
Returns the months component of an
xdt:yearMonthDuration value. |
fn:days-from-duration
|
Returns the days component of an xdt:dayTimeDuration
value. |
fn:hours-from-duration
|
Returns the hours component of an xdt:dayTimeDuration
value. |
fn:minutes-from-duration
|
Returns the minutes component of an xdt:dayTimeDuration
value. |
fn:seconds-from-duration
|
Returns the seconds component of an xdt:dayTimeDuration
value. |
fn:year-from-dateTime
|
Returns the year from an xs:dateTime value. |
fn:month-from-dateTime
|
Returns the month from an xs:dateTime value. |
fn:day-from-dateTime
|
Returns the day from an xs:dateTime value. |
fn:hours-from-dateTime
|
Returns the hours from an xs:dateTime value. |
fn:minutes-from-dateTime
|
Returns the minutes from an xs:dateTime value. |
fn:seconds-from-dateTime
|
Returns the seconds from an xs:dateTime value. |
fn:timezone-from-dateTime
|
Returns the timezone from an xs:dateTime value. |
fn:year-from-date
|
Returns the year from an xs:date value. |
fn:month-from-date
|
Returns the month from an xs:date value. |
fn:day-from-date
|
Returns the day from an xs:date value. |
fn:timezone-from-date
|
Returns the timezone from an xs:date value. |
fn:hours-from-time
|
Returns the hours from an xs:time value. |
fn:minutes-from-time
|
Returns the minutes from an xs:time value. |
fn:seconds-from-time
|
Returns the seconds from an xs:time value. |
fn:timezone-from-time
|
Returns the timezone from an xs:time value. |
Summary: Returns an xs:integer
representing the years component
in the canonical lexical representation of the value of $arg
.
The result may be negative.
If $arg
is the empty sequence, returns the empty sequence.
fn:years-from-duration(xdt:yearMonthDuration("P20Y15M"))
returns 21
.
fn:years-from-duration(xdt:yearMonthDuration("-P15M"))
returns -1
.
Summary: Returns an xs:integer
representing the months component
in the canonical lexical representation of the value of $arg
.
The result may be negative.
If $arg
is the empty sequence, returns the empty sequence.
fn:months-from-duration(xdt:yearMonthDuration("P20Y15M"))
returns 3
.
fn:months-from-duration(xdt:yearMonthDuration("-P20Y18M"))
returns -6
.
Summary: Returns an xs:integer
representing the days component
in the canonical lexical representation of the value of $arg
.
The result may be negative.
If $arg
is the empty sequence, returns the empty sequence.
fn:days-from-duration(xdt:dayTimeDuration("P3DT10H"))
returns 3
.
fn:days-from-duration(xdt:dayTimeDuration("P3DT55H"))
returns 5
.
Summary: Returns an xs:integer
representing the hours component
in the canonical lexical representation of the value of $arg
.
The result may be negative.
If $arg
is the empty sequence, returns the empty sequence.
fn:hours-from-duration(xdt:dayTimeDuration("P3DT10H"))
returns 10
.
fn:hours-from-duration(xdt:dayTimeDuration("P3DT12H32M12S"))
returns 12
.
fn:hours-from-duration(xdt:dayTimeDuration("PT123H"))
returns 3
.
fn:hours-from-duration(xdt:dayTimeDuration("-P3DT10H"))
returns -10
.
Summary: Returns an xs:integer
representing the minutes
component in the canonical lexical representation of the value of
$arg
. The result may be negative.
If $arg
is the empty sequence, returns the empty sequence.
fn:minutes-from-duration(xdt:dayTimeDuration("P3DT10H"))
returns 0
.
fn:minutes-from-duration(xdt:dayTimeDuration("-P5DT12H30M"))
returns -30
.
Summary: Returns an xs:decimal
representing the seconds
component in the canonical lexical representation of the value of
$arg
. The result may be negative.
If $arg
is the empty sequence, returns the empty sequence.
fn:seconds-from-duration(xdt:dayTimeDuration("P3DT10H12.5S"))
returns 12.5
.
fn:seconds-from-duration(xdt:dayTimeDuration("-P256S"))
returns -16.0
.
Summary: Returns an xs:integer
representing the year component
in the localized value of $arg
. The result may be negative.
If $arg
is the empty sequence, returns the empty sequence.
fn:year-from-dateTime(xs:dateTime("1999-05-31T13:20:00-05:00"))
returns 1999
.
fn:year-from-dateTime(xs:dateTime("1999-05-31T21:30:00-05:00"))
returns 1999
.
fn:year-from-dateTime(xs:dateTime("1999-12-31T19:20:00"))
returns 1999
.
fn:year-from-dateTime(xs:dateTime("1999-12-31T24:00:00"))
returns 2000
.
Summary: Returns an xs:integer
between 1 and 12, both inclusive,
representing the month component in the localized value of $arg
.
If $arg
is the empty sequence, returns the empty sequence.
fn:month-from-dateTime(xs:dateTime("1999-05-31T13:20:00-05:00"))
returns 5
.
fn:month-from-dateTime(xs:dateTime("1999-12-31T19:20:00-05:00"))
returns 12
.
fn:month-from-dateTime(fn:adjust-dateTime-to-timezone(xs:dateTime("1999-12-31T19:20:00-05:00"),
xdt:dayTimeDuration("PT0H")))
returns 1
.
Summary: Returns an xs:integer
between 1 and 31, both inclusive,
representing the day component in the localized value of $arg
.
If $arg
is the empty sequence, returns the empty sequence.
fn:day-from-dateTime(xs:dateTime("1999-05-31T13:20:00-05:00"))
returns 31
.
fn:day-from-dateTime(xs:dateTime("1999-12-31T20:00:00-05:00"))
returns 31
.
fn:day-from-dateTime(fn:adjust-dateTime-to-timezone(xs:dateTime("1999-12-31T19:20:00-05:00"),
xdt:dayTimeDuration("PT0H")))
returns 1
.
Summary: Returns an xs:integer
between 0 and 23, both inclusive,
representing the hours component in the localized value of $arg
.
If $arg
is the empty sequence, returns the empty sequence.
fn:hours-from-dateTime(xs:dateTime("1999-05-31T08:20:00-05:00"))
returns 8
.
fn:hours-from-dateTime(xs:dateTime("1999-12-31T21:20:00-05:00"))
returns 21
.
fn:hours-from-dateTime(fn:adjust-dateTime-to-timezone(xs:dateTime("1999-12-31T21:20:00-05:00"),
xdt:dayTimeDuration("PT0H")))
returns
2
.
fn:hours-from-dateTime(xs:dateTime("1999-12-31T12:00:00"))
returns 12
.
fn:hours-from-dateTime(xs:dateTime("1999-12-31T24:00:00"))
returns 0
.
Summary: Returns an xs:integer
value between 0 and 59, both
inclusive, representing the minute component in the localized value of $arg
.
If $arg
is the empty sequence, returns the empty sequence.
fn:minutes-from-dateTime(xs:dateTime("1999-05-31T13:20:00-05:00"))
returns 20
.
fn:minutes-from-dateTime(xs:dateTime("1999-05-31T13:30:00+05:30"))
returns 30
.
Summary: Returns an xs:decimal
value greater than or equal to zero and less than 60,
representing the seconds and fractional seconds in the
localized value of $arg
.
If $arg
is the empty sequence, returns the empty sequence.
fn:seconds-from-dateTime(xs:dateTime("1999-05-31T13:20:00-05:00"))
returns 0
.
Summary: Returns the timezone component of $arg
if any. If
$arg
has a timezone component, then the result is
an xdt:dayTimeDuration
that indicates deviation from UTC; its
value may range from +14:00 to -14:00 hours, both inclusive. Otherwise, the
result is the empty sequence.
If $arg
is the empty sequence, returns the empty sequence.
fn:timezone-from-dateTime(xs:dateTime("1999-05-31T13:20:00-05:00"))
returns the xdt:dayTimeDuration
whose value is
-PT5H
.
fn:timezone-from-dateTime(xs:dateTime("2000-06-12T13:20:00Z"))
returns the xdt:dayTimeDuration
whose value is
-PT0H
.
fn:timezone-from-dateTime(xs:dateTime("2004-08-27T00:00:00"))
returns ()
.
Summary: Returns an xs:integer
representing the year in the
localized value of $arg
. The value may be negative.
If $arg
is the empty sequence, returns the empty sequence.
fn:year-from-date(xs:date("1999-05-31"))
returns
1999
.
fn:year-from-date(xs:date("2000-01-01+05:00"))
returns 2000
.
Summary: Returns an xs:integer
between 1 and 12, both inclusive,
representing the month component in the localized value of
$arg
.
If $arg
is the empty sequence, returns the empty sequence.
fn:month-from-date(xs:date("1999-05-31-05:00"))
returns 5
.
fn:month-from-date(xs:date("2000-01-01+05:00"))
returns 1
.
Summary: Returns an xs:integer
between 1 and 31, both inclusive,
representing the day component in the localized value of $arg
.
If $arg
is the empty sequence, returns the empty sequence.
fn:day-from-date(xs:date("1999-05-31-05:00"))
returns 31
.
fn:day-from-date(xs:date("2000-01-01+05:00"))
returns 1
.
Summary: Returns the timezone component of $arg
if any. If
$arg
has a timezone component, then the result is
an xdt:dayTimeDuration
that indicates deviation from UTC; its
value may range from +14:00 to -14:00 hours, both inclusive. Otherwise, the
result is the empty sequence.
If $arg
is the empty sequence, returns the empty sequence.
fn:timezone-from-date(xs:date("1999-05-31-05:00"))
returns the xdt:dayTimeDuration
whose value is
-PT5H
.
fn:timezone-from-date(xs:date("2000-06-12Z"))
returns the xdt:dayTimeDuration
with value PT0H
.
Summary: Returns an xs:integer
between 0 and 23, both inclusive,
representing the value of the hours component in the localized value of $arg
.
If $arg
is the empty sequence, returns the empty sequence.
Assume that the dynamic context provides an implicit timezone value of -05:00
.
fn:hours-from-time(xs:time("11:23:00"))
returns
11
.
fn:hours-from-time(xs:time("21:23:00"))
returns
21
.
fn:hours-from-time(xs:time("01:23:00+05:00"))
returns 1
.
fn:hours-from-time(fn:adjust-time-to-timezone(xs:time("01:23:00+05:00"),
xdt:dayTimeDuration("PT0H")))
returns 20
.
fn:hours-from-time(xs:time("24:00:00"))
returns 0
.
Summary: Returns an xs:integer
value between 0 and 59, both
inclusive, representing the value of the minutes component in the localized
value of $arg
.
If $arg
is the empty sequence, returns the empty sequence.
fn:minutes-from-time(xs:time("13:00:00Z"))
returns
0
.
Summary: Returns an xs:decimal
value greater than or equal to zero and less than 60, representing the seconds and fractional seconds in the
localized value of $arg
.
If $arg
is the empty sequence, returns the empty sequence.
fn:seconds-from-time(xs:time("13:20:10.5"))
returns
10.5
.
Summary: Returns the timezone component of $arg
if any. If
$arg
has a timezone component, then the result is
an xdt:dayTimeDuration
that indicates deviation from UTC; its
value may range from +14:00 to -14:00 hours, both inclusive. Otherwise, the
result is the empty sequence.
If $arg
is the empty sequence, returns the empty sequence.
fn:timezone-from-time(xs:time("13:20:00-05:00"))
returns xdt:dayTimeDuration
whose value is -PT5H
.
fn:timezone-from-time(xs:time("13:20:00"))
returns ()
.
Function | Meaning |
---|---|
op:add-yearMonthDurations
|
Adds two xdt:yearMonthDuration s. Returns an xdt:yearMonthDuration . |
op:subtract-yearMonthDurations
|
Subtracts one xdt:yearMonthDuration from another.
Returns an xdt:yearMonthDuration . |
op:multiply-yearMonthDuration
|
Multiplies a xdt:yearMonthDuration by an
xs:double . Returns an xdt:yearMonthDuration . |
op:divide-yearMonthDuration
|
Divides an xdt:yearMonthDuration by an
xs:double . Returns an xdt:yearMonthDuration . |
op:divide-yearMonthDuration-by-yearMonthDuration
|
Divides an xdt:yearMonthDuration by an
xdt:yearMonthDuration . Returns an xs:decimal . |
op:add-dayTimeDurations
|
Adds two xdt:dayTimeDurations . Returns an xdt:dayTimeDuration . |
op:subtract-dayTimeDurations
|
Subtracts one xdt:dayTimeDuration from another. Returns
an xdt:dayTimeDuration . |
op:multiply-dayTimeDuration
|
Multiplies an xdt:dayTimeDuration by a
xs:double . Returns an xdt:dayTimeDuration . |
op:divide-dayTimeDuration
|
Divides an xdt:dayTimeDuration by an
xs:double . Returns an xdt:dayTimeDuration . |
op:divide-dayTimeDuration-by-dayTimeDuration
|
Divides an xdt:dayTimeDuration by an
xdt:dayTimeDuration . Returns an xs:decimal . |
Summary: Returns the result of adding the value of $arg1
to the
value of $arg2
. Backs up the "+" operator on
xdt:yearMonthDuration
values.
op:add-yearMonthDurations(xdt:yearMonthDuration("P2Y11M"),
xdt:yearMonthDuration("P3Y3M"))
returns a
xdt:yearMonthDuration
value corresponding to 6
years and 2 months.
Summary: Returns the result of subtracting the value of $arg2
from the value of $arg2
. Backs up the "-" operator on
xdt:yearMonthDuration
values.
op:subtract-yearMonthDurations(xdt:yearMonthDuration("P2Y11M"),
xdt:yearMonthDuration("P3Y3M"))
returns a
xdt:yearMonthDuration
value corresponding to
negative 4 months.
Summary: Returns the result of multiplying the value of $arg1
by
$arg2
. The result is rounded to the nearest month. For a value
If $arg2
is positive or negative zero, the result is a
zero-length duration. If $arg2
is positive or negative
infinity, the result overflows and is handled as discussed in $arg2
is
NaN
an error is raised
Backs up the "*" operator on xdt:yearMonthDuration
values.
op:multiply-yearMonthDuration(xdt:yearMonthDuration("P2Y11M"),
2.3)
returns a xdt:yearMonthDuration
value
corresponding to 6 years and 9 months.
Summary: Returns the result of dividing the value of $arg1
by
$arg2
. The result is rounded to the nearest month. For a value
If $arg2
is positive or negative infinity, the result is a
zero-length duration. If $arg2
is positive or negative zero,
the result overflows and is handled as discussed in $arg2
is
NaN
an error is raised
Backs up the "div" operator on xdt:yearMonthDuration
and numeric values.
op:divide-yearMonthDuration(xdt:yearMonthDuration("P2Y11M"),
1.5)
returns a xdt:yearMonthDuration
value
corresponding to 1 year and 11 months.
Summary: Returns the result of dividing the value of $arg1
by $arg2
. Since the values of both operands are integers, the
semantics of the division is identical to op:numeric-divide
with
xs:integer
operands.
Backs up the "div" operator on xdt:yearMonthDuration
values.
op:divide-yearMonthDuration-by-yearMonthDuration(xdt:yearMonthDuration("P3Y4M"),
xdt:yearMonthDuration("-P1Y4M"))
returns
-2.5
.
Summary: Returns the result of adding the value of $arg1
to the
value of $arg2
. Backs up the "+" operator on
xdt:dayTimeDuration
values.
op:add-dayTimeDurations(xdt:dayTimeDuration("P2DT12H5M"),
xdt:dayTimeDuration("P5DT12H"))
returns a
xdt:dayTimeDuration
value corresponding to 8 days
and 5 minutes.
Summary: Returns the result of subtracting the value of $arg2
from the value of $arg2
. Backs up the "-" operator on
xdt:dayTimeDuration
values.
op:subtract-dayTimeDurations(xdt:dayTimeDuration("P2DT12H"),
xdt:dayTimeDuration("P1DT10H30M"))
returns a
xdt:dayTimeDuration
value corresponding to 1 day, 1
hour and 30 minutes.
Summary: Returns the result of multiplying the value of $arg1
by $arg2
.
If $arg2
is positive or negative zero, the result is a
zero-length duration. If $arg2
is positive or negative
infinity, the result overflows and is handled as discussed in $arg2
is
NaN
an error is raised
Backs up the "*" operator on xdt:dayTimeDuration
values.
op:multiply-dayTimeDuration(xdt:dayTimeDuration("PT2H10M"),
2.1)
returns a xdt:dayTimeDuration
value
corresponding to 4 hours and 33 minutes.
Summary: Returns the result of dividing the value of $arg1
by
$arg2
.
If $arg2
is positive or negative infinity, the result is a
zero-length duration. If $arg2
is positive or negative zero,
the result overflows and is handled as discussed in $arg2
is
NaN
an error is raised
Backs up the "div" operator on xdt:dayTimeDuration
values.
op:divide-dayTimeDuration(xdt:yearMonthDuration("P1DT2H30M10.5S"),
1.5)
returns a xdt:dayTimeDuration
value
corresponding to 17 hours, 40 minutes and 7 seconds.
Summary: Returns the result of dividing the value of $arg1
by $arg2
. Since the values of both operands are decimals, the
semantics of the division is identical to op:numeric-divide
with
xs:decimal
operands.
Backs up the "div" operator on xdt:dayTimeDuration
values.
op:divide-dayTimeDuration-by-dayTimeDuration(xdt:dayTimeDuration("P2DT53M11S"),
xdt:dayTimeDuration("P1DT10H))
returns 1.4378349...
Function | Meaning |
---|---|
fn:adjust-dateTime-to-timezone
|
Adjusts an xs:dateTime value to a specific timezone, or
to no timezone at all. |
fn:adjust-date-to-timezone
|
Adjusts an xs:date value to a specific timezone, or to
no timezone at all. |
fn:adjust-time-to-timezone
|
Adjusts an xs:time value to a specific timezone, or to
no timezone at all. |
These functions adjust the timezone component of an xs:dateTime
, xs:date
or
xs:time
value. The $timezone
argument to these functions is defined as an xdt:dayTimeDuration
but must be a valid timezone value.
Summary: Adjusts an xs:dateTime
value to a specific timezone, or
to no timezone at all. If $timezone
is the empty sequence,
returns an xs:dateTime
without a timezone. Otherwise, returns
an xs:dateTime
with a timezone.
If $timezone
is not specified, then $timezone
is
the value of the implicit timezone in the dynamic context.
If $arg
is the empty sequence, then the result is the empty sequence.
A dynamic error is raised $timezone
is less than -PT14H
or greater than PT14H
or if does not contain an integral number of minutes.
If $arg
does not have a timezone component and
$timezone
is the empty sequence, then the result is $arg
.
If $arg
does not have a timezone component and
$timezone
is not the empty sequence, then the result is
$arg
with $timezone
as the timezone component.
If $arg
has a timezone component and $timezone
is
the empty sequence, then the result is the localized value of
$arg
without its timezone component.
If $arg
has a timezone component and $timezone
is
not the empty sequence, then the result is an xs:dateTime
value
with a timezone component of $timezone
that is equal to $arg
.
Assume the dynamic context provides an implicit timezone of -05:00 (-PT5H0M)
.
let $tz := xdt:dayTimeDuration("-PT10H")
fn:adjust-dateTime-to-timezone(xs:dateTime("2002-03-07T10:00:00"))
returns 2002-03-07T10:00:00-05:00
fn:adjust-dateTime-to-timezone(xs:dateTime("2002-03-07T10:00:00-07:00"))
returns 2002-03-07T12:00:00-05:00
fn:adjust-dateTime-to-timezone(xs:dateTime("2002-03-07T10:00:00"),
$tz)
returns 2002-03-07T10:00:00-10:00
fn:adjust-dateTime-to-timezone(xs:dateTime("2002-03-07T10:00:00-07:00"),
$tz)
returns 2002-03-07T07:00:00-10:00
fn:adjust-dateTime-to-timezone(xs:dateTime("2002-03-07T10:00:00-07:00"),
xdt:dayTimeDuration("PT10H"))
returns 2002-03-08T03:00:00+10:00
fn:adjust-dateTime-to-timezone(xs:dateTime("2002-03-07T00:00:00+01:00"),
xdt:dayTimeDuration("-PT8H"))
returns 2002-03-06T15:00:00-08:00
fn:adjust-dateTime-to-timezone(xs:dateTime("2002-03-07T10:00:00"),
())
returns 2002-03-07T10:00:00
fn:adjust-dateTime-to-timezone(xs:dateTime("2002-03-07T10:00:00-07:00"),
())
returns 2002-03-07T10:00:00
Summary: Adjusts an xs:date
value to a specific timezone, or to
no timezone at all. If $timezone
is the empty sequence, returns
an xs:date
without a timezone. Otherwise, returns an
xs:date
with a timezone. For purposes of timezone adjustment,
an xs:date
is treated as an xs:dateTime
with time 00:00:00
.
If $timezone
is not specified, then $timezone
is
the value of the implicit timezone in the dynamic context.
If $arg
is the empty sequence, then the result is the empty sequence.
A dynamic error is raised $timezone
is less than -PT14H
or greater than PT14H
or if does not contain an integral number of minutes.
If $arg
does not have a timezone component and
$timezone
is the empty sequence, then the result is the value
of $arg
.
If $arg
does not have a timezone component and
$timezone
is not the empty sequence, then the result is
$arg
with $timezone
as the timezone component.
If $arg
has a timezone component and $timezone
is
the empty sequence, then the result is the localized value of
$arg
without its timezone component.
If $arg
has a timezone component and $timezone
is
not the empty sequence, then:
Let $srcdt
be an xs:dateTime
value, with
00:00:00
for the time component and date and timezone
components that are the same as the date and timezone components of $arg
.
Let $r
be the result of evaluating
fn:adjust-dateTime-to-timezone($srcdt, $timezone)
The result of this function will be a date value that has date and
timezone components that are the same as the date and timezone
components of $r
.
Assume the dynamic context provides an implicit timezone of -05:00 (-PT5H0M)
.
let $tz := xdt:dayTimeDuration("-PT10H")
fn:adjust-date-to-timezone(xs:date("2002-03-07"))
returns 2002-03-07-05:00.
fn:adjust-date-to-timezone(xs:date("2002-03-07-07:00"))
returns 2002-03-07-05:00
.$arg
is
converted to the xs:dateTime
"2002-03-07T00:00:00-07:00"
. This is adjusted to the
implicit timezone, giving "2002-03-07T02:00:00-05:00".
fn:adjust-date-to-timezone(xs:date("2002-03-07"),
$tz)
returns 2002-03-07-10:00
.
fn:adjust-date-to-timezone(xs:date("2002-03-07-07:00"),
$tz)
returns 2002-03-06-10:00
.
$arg
is converted to the xs:dateTime
"2002-03-07T00:00:00-07:00"
. This is adjusted to the
given timezone, giving "2002-03-06T21:00:00-10:00"
.
fn:adjust-date-to-timezone(xs:date("2002-03-07"),
())
returns 2002-03-07.
fn:adjust-date-to-timezone(xs:date("2002-03-07-07:00"),
())
returns 2002-03-07.
Summary: Adjusts an xs:time
value to a specific timezone, or to
no timezone at all. If $timezone
is the empty sequence, returns
an xs:time
without a timezone. Otherwise, returns an
xs:time
with a timezone.
If $timezone
is not specified, then $timezone
is
the value of the implicit timezone in the dynamic context.
If $arg
is the empty sequence, then the result is the empty sequence.
A dynamic error is raised $timezone
is less than -PT14H
or greater than PT14H
or if does not contain an integral number of minutes.
If $arg
does not have a timezone component and
$timezone
is the empty sequence, then the result is $arg
.
If $arg
does not have a timezone component and
$timezone
is not the empty sequence, then the result is
$arg
with $timezone
as the timezone component.
If $arg
has a timezone component and $timezone
is
the empty sequence, then the result is the localized value of
$arg
without its timezone component.
If $arg
has a timezone component and $timezone
is
not the empty sequence, then:
Let $srcdt
be an xs:dateTime
value, with
an arbitrary date for the date component and time and timezone
components that are the same as the time and timezone components of $arg
.
Let $r
be the result of evaluating
fn:adjust-dateTime-to-timezone($srcdt, $timezone)
The result of this function will be a time value that has time and
timezone components that are the same as the time and timezone
components of $r
.
Assume the dynamic context provides an implicit timezone of -05:00 (-PT5H0M)
.
let $tz := xdt:dayTimeDuration("-PT10H")
fn:adjust-time-to-timezone(xs:time("10:00:00"))
returns 10:00:00-05:00
fn:adjust-time-to-timezone(xs:time("10:00:00-07:00"))
returns 12:00:00-05:00
fn:adjust-time-to-timezone(xs:time("10:00:00"),
$tz)
returns 10:00:00-10:00
fn:adjust-time-to-timezone(xs:time("10:00:00-07:00"),
$tz)
returns 07:00:00-10:00
fn:adjust-time-to-timezone(xs:time("10:00:00"), ())
returns 10:00:00
fn:adjust-time-to-timezone(xs:time("10:00:00-07:00"),
())
returns 10:00:00
fn:adjust-time-to-timezone(xs:time("10:00:00-07:00"),
xdt:dayTimeDuration("PT10H"))
returns 03:00:00+10:00
These functions support adding or subtracting a duration value to or from an
xs:dateTime
, an xs:date
or an xs:time
value. Appendix E of
Function | Meaning |
---|---|
op:subtract-dateTimes
|
Returns the difference between two xs:dateTimes as an xdt:dayTimeDuration . |
op:subtract-dates
|
Returns the difference between two xs:dateTimes as an xdt:dayTimeDuration . |
op:subtract-times
|
Returns the difference between two xs:time s as an xdt:dayTimeDuration . |
op:add-yearMonthDuration-to-dateTime
|
Returns the end of a time period by adding an
xdt:yearMonthDuration to the xs:dateTime
that starts the period. |
op:add-dayTimeDuration-to-dateTime
|
Returns the end of a time period by adding an
xdt:dayTimeDuration to the xs:dateTime
that starts the period. |
op:subtract-yearMonthDuration-from-dateTime
|
Returns the beginning of a time period by subtracting an
xdt:yearMonthDuration from the xs:dateTime
that ends the period. |
op:subtract-dayTimeDuration-from-dateTime
|
Returns the beginning of a time period by subtracting an
xdt:dayTimeDuration from the xs:dateTime
that ends the period. |
op:add-yearMonthDuration-to-date
|
Returns the end of a time period by adding an
xdt:yearMonthDuration to the xs:date that
starts the period. |
op:add-dayTimeDuration-to-date
|
Returns the end of a time period by adding an
xdt:dayTimeDuration to the xs:date that
starts the period. |
op:subtract-yearMonthDuration-from-date
|
Returns the beginning of a time period by subtracting an
xdt:yearMonthDuration from the xs:date
that ends the period. |
op:subtract-dayTimeDuration-from-date
|
Returns the beginning of a time period by subtracting an
xdt:dayTimeDuration from the xs:date that
ends the period. |
op:add-dayTimeDuration-to-time
|
Adds the value of the hours, minutes and seconds components of an
xdt:dayTimeDuration to an xs:time value. |
op:subtract-dayTimeDuration-from-time
|
Subtracts the value of the hours, minutes and seconds components of
an xdt:dayTimeDuration to an xs:time value. |
Summary: Returns the xdt:dayTimeDuration
that corresponds to the
difference between the normalized value of $arg1
and the
normalized value of $arg2
. If either $arg1
or $arg2
do not contain an explicit timezone then, for the
purpose of the operation, the implicit timezone provided by the dynamic
context (See
If the normalized value of $arg1
precedes in time the normalized
value of $arg2
, then the returned value is a negative duration.
Backs up the subtract, "-", operator on xs:dateTime
values.
Assume that the dynamic context provides an implicit timezone value of -05:00
.
op:subtract-dateTimes(xs:dateTime("2000-10-30T06:12:00"),
xs:dateTime("1999-11-28T09:00:00Z"))
returns an
xdt:dayTimeDuration
value corresponding to 337
days, 2 hours and 12 minutes.
Summary: Returns the xdt:dayTimeDuration
that corresponds to the
difference between the starting instant of $arg1
and the
the starting instant of $arg2
. If either $arg1
or $arg2
do not contain an explicit timezone then, for the
purpose of the operation, the implicit timezone provided by the dynamic
context (See
The starting instant of an xs:date
is the xs:dateTime
at 00:00:00
on that date.
The result is the result of subtracting the two starting instants using
op:subtract-dateTimes
.
If the starting instant of $arg1
precedes in time the starting instant of $arg2
, then the returned value is a negative duration.
Backs up the subtract, "-", operator on xs:date
values.
Assume that the dynamic context provides an implicit timezone value of Z
. op:subtract-dates(xs:date("2000-10-30"), xs:date("1999-11-28"))
returns an
xdt:dayTimeDuration
value corresponding to 337 days. The normalized values of the two starting instants are {2000, 10, 30, 0, 0, 0, PT0S}
and {1999, 11, 28, 0, 0, 0, PT0S}
.
If the dynamic context provides an implicit timezone value
of +05:00
,
op:subtract-dates(xs:date("2000-10-30"),
xs:date("1999-11-28Z"))
returns an
xdt:dayTimeDuration
value corresponding to 335 days and 19 hours. The normalized values of the two starting instants are {2000, 10, 29, 19, 0, 0, PT0S}
and {1999, 11, 28, 0, 0, 0, PT0S}
.
op:subtract-dates(xs:date("2000-10-15-05:00"),
xs:date("2000-10-10+02:00"))
returns an
xdt:dayTimeDuration
value corresponding to lexical form "P5DT7H
".
Summary: Returns the xdt:dayTimeDuration
that corresponds to the
difference between the value of $arg1
converted to an xs:dateTime
using the date components from the reference xs:dateTime
and the
value of $arg2
converted to an xs:dateTime
using the date components from the same reference xs:dateTime
. If either $arg1
or $arg2
do not contain an explicit timezone then, for the
purpose of the operation, the implicit timezone provided by the dynamic
context (See
The result is the result of subtracting the two xs:dateTime
s using
op:subtract-dateTimes
.
If the value of $arg1
converted to an xs:dateTime
using the date components from the reference xs:dateTime
precedes in time the
value of $arg2
converted to an xs:dateTime
using the date components from the same reference xs:dateTime
, then the returned value is a negative duration.
Backs up the subtract, "-", operator on xs:time
values.
Assume that the dynamic context provides an implicit timezone value of -05:00
. Assume, also, that the date components of the reference xs:dateTime
correspond to "1972-12-31"
.
op:subtract-times(xs:time("11:12:00Z"),
xs:time("04:00:00"))
returns an
xdt:dayTimeDuration
value corresponding to 2 hours
and 12 minutes. This is obtained by subtracting from the xs:dateTime
value {1972, 12, 31, 11, 12, 0, PT0S}
the xs:dateTime
value {1972, 12, 31, 9, 0, 0, PT0S}
.
op:subtract-times(xs:time("11:00:00-05:00"),
xs:time("21:30:00+05:30"))
returns a zero
xdt:dayTimeDuration
value corresponding to the lexical representation "PT0S"
. The two xs:dateTime
values are {1972, 12, 31, 11, 0, 0, -PT5H}
and {1972, 12, 31, 21, 30, 0, PT5H30M}
.
These normalize to {1972, 12, 31, 16, 0, 0, PT0S}
and {1972, 12, 31, 16, 0, 0, PT0S}
.
op:subtract-times(xs:time("17:00:00-06:00"),
xs:time("08:00:00+09:00"))
returns an
xdt:dayTimeDuration
value corresponding to one day or 24 hours. The two normalized xs:dateTime
values are {1972, 12, 31, 23, 0, 0, PT0S}
and {1972, 12, 30, 23, 0, 0, PT0S}
.
op:subtract-times(xs:time("24:00:00"), xs:time("23:59:59"))
returns an
xdt:dayTimeDuration
value corresponding to "-PT23H59M59S"
. The two normalized xs:dateTime
values are {1972, 12, 31, 0, 0, 0, ()}
and {1972, 12, 31, 23, 59, 59.0, ()}
.
Summary: Returns the xs:dateTime
computed by adding
$arg2
to the value of $arg1
using the
algorithm described in Appendix E of $arg2
is negative, then the result xs:dateTime
precedes $arg1
.
The result has the same timezone as $arg1
. If $arg1
has no timezone, the result has no timezone.
This functions backs up the "+" operator on xs:dateTime
and
xdt:yearMonthDuration
values.
op:add-yearMonthDuration-to-dateTime(xs:dateTime("2000-10-30T11:12:00"),
xdt:yearMonthDuration("P1Y2M"))
returns an
xs:dateTime
value corresponding to the lexical
representation "2001-12-30T11:12:00"
.
Summary: Returns the xs:dateTime
computed by adding
$arg2
to the value of $arg1
using the
algorithm described in Appendix E of $arg2
is negative, then the result xs:dateTime
precedes $arg1
.
The result has the same timezone as $arg1
. If $arg1
has no timezone, the result has no timezone.
This functions backs up the "+" operator on xs:dateTime
and
xdt:dayTimeDuration
values.
op:add-dayTimeDuration-to-dateTime(xs:dateTime("2000-10-30T11:12:00"),
xdt:dayTimeDuration("P3DT1H15M"))
returns an
xs:dateTime
value corresponding to the lexical
representation "2000-11-02T12:27:00"
.
Summary: Returns the xs:dateTime
computed by negating
$arg2
and adding the result to the value of
$arg1
using the algorithm described in Appendix E of $arg2
is negative, then the
xs:dateTime
returned follows $arg1
.
The result has the same timezone as $arg1
. If $arg1
has no timezone, the result has no timezone.
This functions backs up the "-" operator on xs:dateTime
and
xdt:yearMonthDuration
values.
op:subtract-yearMonthDuration-from-dateTime(xs:dateTime("2000-10-30T11:12:00"),
xdt:yearMonthDuration("P1Y2M"))
returns an
xs:dateTime
value corresponding to the lexical
representation "1999-08-30T11:12:00"
.
Summary: Returns the xs:dateTime
computed by negating
$arg2
and adding the result to the value of
$arg1
using the algorithm described in Appendix E of $arg2
is negative, then the
xs:dateTime
returned follows $arg1
.
The result has the same timezone as $arg1
. If $arg1
has no timezone, the result has no timezone.
This functions backs up the "-" operator on xs:dateTime
and
xdt:dayTimeDuration
values.
op:subtract-dayTimeDuration-from-dateTime(xs:dateTime("2000-10-30T11:12:00"),
xdt:dayTimeDuration("P3DT1H15M"))
returns an
xs:dateTime
value corresponding to the lexical
representation "2000-10-27T09:57:00"
.
Summary: Returns the xs:date
computed by adding
$arg2
to the starting instant of $arg1
using the
algorithm described in Appendix E of xs:dateTime
. If
$arg2
is negative, then the xs:date
returned
precedes $arg1
.
The starting instant of an xs:date
is the xs:dateTime
at time 00:00:00
on that date.
The result has the same timezone as $arg1
. If $arg1
has no timezone, the result has no timezone.
This functions backs up the "+" operator on xs:date
and
xdt:yearMonthDuration
values.
op:add-yearMonthDuration-to-date(xs:date("2000-10-30"),
xdt:yearMonthDuration("P1Y2M"))
returns
the xs:date
corresponding to December 30, 2001.
Summary: Returns the xs:date
computed by adding
$arg2
to the starting instant of $arg1
using the
algorithm described in Appendix E of xs:dateTime
. If
$arg2
is negative, then the xs:date
returned
precedes $arg1
.
The starting instant of an xs:date
is the xs:dateTime
at time 00:00:00
on that date.
The result has the same timezone as $arg1
. If $arg1
has no timezone, the result has no timezone.
This functions backs up the "+" operator on xs:date
and
xdt:dayTimeDuration
values.
op:add-dayTimeDuration-to-date(xs:date("2004-10-30Z"),
xdt:dayTimeDuration("P2DT2H30M0S"))
returns the
xs:date
November 1, 2004. The starting instant of the first argument is the xs:dateTime
value {2004, 10, 30, 0, 0, 0, PT0S}
. Adding the second argument to this, gives the xs:dateTime
value {2004, 11, 1, 2, 30, 0, PT0S}
. The time components are then discarded.
Summary: Returns the xs:date
computed by negating
$arg2
and adding the result to the starting instant of
$arg1
using the algorithm described in Appendix E of xs:dateTime
. If $arg2
is positive, then the
xs:date
returned precedes $arg1
.
The starting instant of an xs:date
is the xs:dateTime
at 00:00:00
on that date.
The result has the same timezone as $arg1
. If $arg1
has no timezone, the result has no timezone.
This functions backs up the "-" operator on xs:date
and
xdt:yearMonthDuration
values.
op:subtract-yearMonthDuration-from-date(xs:date("2000-10-30"),
xdt:yearMonthDuration("P1Y2M"))
returns the
xs:date
August 30, 1999.
op:subtract-yearMonthDuration-from-date(xs:date("2000-02-29Z"),
xdt:yearMonthDuration("P1Y"))
returns the
xs:date
February 28,
1999 in timezone Z
.
op:subtract-yearMonthDuration-from-date(xs:date("2000-10-31-05:00"),
xdt:yearMonthDuration("P1Y1M"))
returns the
xs:date
September 30,
1999 in timezone -05:00
.
Summary: Returns the xs:date
computed by negating
$arg2
and adding the result to the starting instant of
$arg1
using the algorithm described in Appendix E of xs:dateTime
. If $arg2
is positive, then the
xs:date
returned precedes $arg1
.
The starting instant of an xs:date
is the xs:dateTime
at 00:00:00
on that date.
The result has the same timezone as $arg1
. If $arg1
has no timezone, the result has no timezone.
This functions backs up the "-" operator on xs:date
and
xdt:dayTimeDuration
values.
op:subtract-dayTimeDuration-from-date(xs:date("2000-10-30"),
xdt:dayTimeDuration("P3DT1H15M"))
returns the
xs:date
October 26, 2000.
Summary: First, the days component in the canonical lexical representation of
$arg2
is set to zero (0) and the value of the resulting
xdt:dayTimeDuration
is calculated. Alternatively, the value of $arg2
modulus 86,400 is used as the second argument. This value is added to the value of
$arg1
converted to an xs:dateTime
using a reference date such as 1972-12-31
and the time components of the result returned. Note that the
xs:time
returned may occur in a following or preceding day and
may be less than $arg1
.
The result has the same timezone as $arg1
. If $arg1
has no timezone, the result has no timezone.
This functions backs up the "+" operator on xs:time
and
xdt:dayTimeDuration
values.
op:add-dayTimeDuration-to-time(xs:time("11:12:00"),
xdt:dayTimeDuration("P3DT1H15M"))
returns the
xs:time
value corresponding to the lexical
representation "12:27:00
".
op:add-dayTimeDuration-to-time(xs:time("23:12:00+03:00"),
xdt:dayTimeDuration("P1DT3H15M"))
returns the
xs:time
value corresponding to the lexical
representation "02:27:00+03:00
", i.e. {0, 0, 0, 2, 27, 0, PT3H}
.
Summary: The result is calculated by first setting the day component in the
canonical lexical representation of $arg2
to zero (0) and
calculating the value of the resulting xdt:dayTimeDuration
.
Alternatively, the value of $arg2
modulus 86,400 is used as the second argument. This
value is subtracted from the value of $arg1
converted to an xs:dateTime
using a reference date such as 1972-12-31
and the time components of the
result are returned. Note that the xs:time
returned may occur in
a preceding or following day and may be greater than $arg1
.
The result has the same timezone as $arg1
. If $arg1
has no timezone, the result has no timezone.
This functions backs up the "-" operator on xs:time
and
xdt:dayTimeDuration
values.
op:subtract-dayTimeDuration-from-time(xs:time("11:12:00"),
xdt:dayTimeDuration("P3DT1H15M"))
returns an
xs:time
value corresponding to the lexical
representation "09:57:00"
.
op:subtract-dayTimeDuration-from-time(xs:time("08:20:00-05:00"),
xdt:dayTimeDuration("P23DT10H10M"))
returns the
xs:time
value corresponding to the lexical
representation "22:10:00-05:00"
i.e. {0, 0, 0, 22, 10, 0, -PT5H}
This section
defines additional constructor functions for QName as defined in
Function | Meaning | |
---|---|---|
fn:resolve-QName
|
Returns an xs:QName with the lexical form given in the
first argument. The prefix is resolved using the in-scope namespaces
for a given element. |
|
fn:QName
|
Returns an xs:QName with the namespace URI given in the
first argument and the local name and prefix in the second argument. |
Summary: Returns an xs:QName
value (that is, an expanded-QName)
by taking an xs:string
that has the lexical form of an
xs:QName
(a string in the form "prefix:local-name" or
"local-name") and resolving it using the in-scope namespaces for a given element.
If $qname
does not have the correct lexical form
for xs:QName
an error is raised
If $qname
is the empty sequence, returns the empty sequence.
More specifically, the function searches the namespace bindings of
$element
for a binding whose name matches the prefix of
$qname
, or the zero-length string if it has no prefix, and
constructs an expanded-QName whose local name is taken from the supplied
$qname
, and whose namespace URI is taken from the string value
of the namespace binding.
If the $qname
has a prefix and if there is no namespace binding
for $element
that matches this prefix, then an error is raised
If the $qname
has no prefix, and there is no namespace binding for
$element
corresponding to the default (unnamed) namespace, then
the resulting expanded-QName has no namespace part.
The prefix (or absence of a prefix) in the supplied $qname
argument is retained in the returned expanded-QName, as discussed in
Sometimes the requirement is to construct an xs:QName
without using the default namespace. This can be achieved by writing:
If the requirement is to construct an xs:QName
using the
namespaces in the static context, then the xs:QName
constructor should be used.
Assume that the element bound to $element
has a single
namespace binding bound to the prefix eg
.
fn:resolve-QName("hello", $element)
returns a QName
with local name "hello" that is in no namespace.
fn:resolve-QName("eg:myFunc", $element)
returns an
xs:QName
whose namespace URI is specified by the
namespace binding corresponding to the prefix "eg" and whose local
name is "myFunc".
Summary: Returns an xs:QName
with the namespace URI given in
$paramURI
. If $paramURI
is the zero-length string or the
empty sequence, it represents "no namespace"; in this case, if the value
of $paramQName
contains a colon (:
),
an error is raised $paramQName
is retained in the returned
xs:QName
value. The local name in the result is taken from the
local part of $paramQName
.
If $paramQName
does not have the correct lexical form
for
xs:QName
an error is raised
Note that unlike xs:QName
this function does not require
a xs:string
literal as the argument.
fn:QName("http://www.example.com/example",
"person")
returns an xs:QName
with namespace
URI = "http://www.example.com/example", local name = "person"
and prefix = "".
fn:QName("http://www.example.com/example",
"ht:person")
returns an xs:QName
with
namespace URI = "http://www.example.com/example", local name =
"person" and prefix = "ht".
This section discusses functions on QNames as defined in
Function | Meaning |
---|---|
op:QName-equal
|
Returns true if the local names and namespace URIs of
the two arguments are equal. |
fn:prefix-from-QName
|
Returns an xs:NCName representing the prefix of the
xs:QName argument. |
fn:local-name-from-QName
|
Returns an xs:NCName representing the local name of the
xs:QName argument. |
fn:namespace-uri-from-QName
|
Returns the namespace URI for the xs:QName argument. If
the xs:QName is in no namespace, the zero-length string
is returned. |
fn:namespace-uri-for-prefix
|
Returns the namespace URI of one of the in-scope namespaces for the given element, identified by its namespace prefix. |
fn:in-scope-prefixes
|
Returns the prefixes of the in-scope namespaces for the given element. |
Summary: Returns true
if the namespace URIs of
$arg1
and $arg2
are equal and the local names of
$arg1
and $arg2
are identical based on the default
collation. Otherwise, returns false
. Two namespace URIs are
considered equal if they are either both absent or both present and
identical based on the Unicode code point
collation (http://www.w3.org/2005/xpath-functions/collation/codepoint
). The prefix parts of
$arg1
and $arg2
, if any, are ignored.
Backs up the "eq" and "ne" operators on values of type xs:QName
.
Summary: Returns an xs:NCName
representing the prefix of
$arg
. The empty sequence is returned if $arg
is the empty sequence or if the value of $arg
contains no prefix.
Summary: Returns an xs:NCName
representing the local part of
$arg
. If $arg
is the empty sequence, returns the
empty sequence.
fn:local-name-from-QName(fn:QName("http://www.example.com/example",
"person"))
returns "person"
.
Summary: Returns the namespace URI for $arg
as an
xs:string
. If $arg
is the empty sequence, the
empty sequence is returned. If $arg
is in no namespace, the
zero-length string is returned.
fn:namespace-uri-from-QName(fn:QName("http://www.example.com/example",
"person"))
returns the namespace URI corresponding to
"http://www.example.com/example"
.
Summary: Returns the namespace URI of one of the in-scope namespaces for
$element
, identified by its namespace prefix.
If $element
has an in-scope namespace whose namespace prefix is
equal to $prefix
, it returns the namespace URI of that
namespace. If $prefix
is the zero-length string or the empty sequence, it returns the
namespace URI of the default (unnamed) namespace. Otherwise, it returns the
empty sequence.
Prefixes are equal only if their Unicode code points match exactly.
Summary: Returns the prefixes of the in-scope namespaces for
$element
. For namespaces that have a prefix, it returns the
prefix as an xs:NCName
. For the default namespace, which has no
prefix, it returns the zero-length string.
The following comparison operators on xs:base64Binary
and
xs:hexBinary
values are defined. Comparisons take two operands of
the same type; that is, both operands must be xs:base64Binary
or
both operands may be xs:hexBinary
. Each returns a boolean value.
A value of type xs:hexBinary
can be compared with a value of type
xs:base64Binary
by casting one value to the other type. See
Function | Meaning |
---|---|
op:hexBinary-equal
|
Returns true if the two arguments are equal. |
op:base64Binary-equal
|
Returns true if the two arguments are equal. |
Summary: Returns true
if $value1
and
$value2
are of the same length, measured in binary octets, and
contain the same octets in the same order. Otherwise, returns
false
.
This function backs up the "eq" and "ne" operators on
xs:hexBinary
values.
Summary: Returns true
if $value1
and
$value2
are of the same length, measured in binary octets, and
contain the same octets in the same order. Otherwise, returns false
.
This function backs up the "eq" and "ne" operators on
xs:base64Binary
values.
This section discusses functions that take NOTATION as arguments.
Function | Meaning |
---|---|
op:NOTATION-equal
|
Returns true if the two arguments are equal. |
Summary: Returns true
if $arg1
and
$arg2
compare equal on a codepoint-by-codepoint basis. Else
returns false
. This function backs up the "eq" and "ne"
operators on xs:NOTATION
values.
This section discusses functions and operators on nodes. Nodes are formally defined
in
Function | Meaning | |
---|---|---|
fn:name
|
Returns the name of the context node or the specified node as an
xs:string . |
|
fn:local-name
|
Returns the local name of the context node or the specified node as an
xs:NCName . |
|
fn:namespace-uri
|
Returns the namespace URI as an xs:anyURI for the
xs:QName of the argument node or the context node if the
argument is omitted. This may be the URI corresponding to the
zero-length string if the xs:QName is in no namespace. |
|
fn:number
|
Returns the value of the context item after atomization or the specified
argument converted to an xs:double . |
|
fn:lang
|
Returns true or false , depending on whether the
language of the given node or the context node, as defined using the
xml:lang attribute, is the same as, or a sublanguage of, the language
specified by the argument. |
|
op:is-same-node
|
Returns true if the two arguments have the same identity. |
|
op:node-before
|
Indicates whether one node appears before another node in document order. | |
op:node-after
|
Indicates whether one node appears after another node in document order. | |
fn:root
|
Returns the root of the tree to which the node argument belongs. |
For the illustrative examples below assume an XQuery or transformation operating on a
PurchaseOrder document containing a number of line-item elements. Each line-item has
child elements called description, price, quantity, etc. whose content is different
for each line-item. Quantity has simple content of type xs:decimal
.
Further assume that variables $item1
, $item2
, etc. are
each bound to single line-item element nodes in the document in sequence and that
the value of the quantity child of the first line-item is 5.0
.
Summary: Returns the name of a node, as an xs:string
that is either
the zero-length string, or has the lexical form of an xs:QName
.
If the argument is omitted, it defaults to the context node. If the context item
is undefined an error is raised:
If the argument is supplied and is the empty sequence, the function returns the zero-length string.
If the target node has no name (that is, if it is a document node, a comment, a text node, or a namespace binding having no name), the function returns the zero-length string.
Otherwise, the value returned is fn:string(fn:node-name($arg))
.
Summary: Returns the local part of the name of $arg
as an
xs:string
that will either be the zero-length string or will have
the lexical form of an xs:NCName
.
If the argument is omitted, it defaults to the context node. If the context item
is undefined an error is raised:
If the argument is supplied and is the empty sequence, the function returns the zero-length string.
If the target node has no name (that is, if it is a document node, a comment, or a text node), the function returns the zero-length string.
Otherwise, the value returned will be the local part of the expanded-QName of the
target node (as determined by the dm:node-name
accessor in xs:string
whose
lexical form is an xs:NCName
.
Summary: Returns the namespace URI of the xs:QName
of $arg
.
If the argument is omitted, it defaults to the context node. If the context item
is undefined an error is raised:
If $arg
is the empty sequence, the xs:anyURI
corresponding to the zero-length string is returned.
If $arg
is neither an element nor an attribute node, or if it is an
element or attribute node whose expanded-QName (as determined by the
dm:node-name
accessor in the xs:anyURI
corresponding to the zero-length string.
Summary: Returns the value indicated by $arg
or, if
$arg
is not specified, the context item after atomization,
converted to an xs:double
. If $arg
is the empty
sequence or if $arg
or the context item cannot be converted to an
xs:double
, the xs:double
value NaN
is
returned. If the context item is undefined an error is raised:
Calling the zero-argument version of the function is defined to give the same
result as calling the single-argument version with an argument of ".". That is,
fn:number()
is equivalent to fn:number(.)
.
If $arg
is the empty sequence, NaN
is returned.
Otherwise, $arg
, or the context item after atomization, is
converted to an xs:double
following the rules of xs:double
fails,
the xs:double
value NaN
is returned.
fn:number($item1/quantity)
returns 5.0
.
fn:number($item2)
returns NaN
.
Assume that the context item is the xs:string
"15
". fn:number()
returns 1.5E1
.
Summary: This function tests whether the language of $node
, or the
context node if the second argument is omitted, as specified by
xml:lang
attributes is the same as, or is a sublanguage of, the
language specified by $testlang
. The language of the argument node,
or the context node if the second argument is omitted, is determined by the
value of the xml:lang
attribute on the node, or, if the node has no
such attribute, by the value of the xml:lang
attribute on the
nearest ancestor of the node that has an xml:lang
attribute. If
there is no such ancestor, then the function returns false
If the second argument is omitted and the context item is undefined an error is
raised:
If $testlang
is the empty sequence it is interpreted as the
zero-length string.
The relevant xml:lang
attribute is determined by the value of the
XPath expression:
If this expression returns an empty sequence, the function returns
false
.
Otherwise, the function returns true
if and only if the string-value
of the relevant xml:lang
attribute is equal
to $testlang
based on a caseless default match as specified in
section 3.13 of testlang
attribute contains a hyphen, "-" (The character "-" is
HYPHEN-MINUS, #x002D) such that the part of the string-value preceding that
hyphen is equal to $testlang
, using caseless matching.
The expression fn:lang("en")
would return
true
if the context node were any of the following four elements:
<para xml:lang="en"/>
<div xml:lang="en"><para>And now,
and forever!</para></div>
<para xml:lang="EN"/>
<para xml:lang="en-us"/>
The expression fn:lang("fr")
would return
false
if the context node were <para xml:lang="EN"/>
Summary: If the node identified by the value of $parameter1
is the
same node as the node identified by the value of $parameter2
(that
is, the two nodes have the same identity), then the function returns
true
; otherwise, the function returns false
. This
function backs up the "is" operator on nodes.
op:is-same-node($item1, $item1)
returns
true
.
op:is-same-node($item1, $item2)
returns
false
.
Summary: If the node identified by the value of $parameter1
occurs
in document order before the node identified by the value of
$parameter2
, this function returns true
; otherwise, it
returns false
. The rules determining the order of nodes within a
single document and in different documents can be found in
op:node-before($item1, $item2)
returns
true
.
op:node-before($item1, $item1)
returns
false
.
Summary: If the node identified by the value of $parameter1
occurs
in document order after the node identified by the value of
$parameter2
, this function returns true
; otherwise, it
returns false
. The rules determining the order of nodes within a
single document and in different documents can be found in
op:node-after($item1, $item2)
returns
false
.
op:node-after($item1, $item1)
returns
false
.
op:node-after($item2, $item1)
returns
true
.
Summary: Returns the root of the tree to which $arg
belongs. This
will usually, but not necessarily, be a document node.
If $arg
is the empty sequence, the empty sequence is returned.
If $arg
is a document node, $arg
is returned.
If the function is called without an argument, the context item is used as the
default argument. If the context item is undefined an error is raised:
These examples use some variables which could be defined in
Or they could be defined in
fn:root($i)
returns $i
fn:root($o/quantity)
returns $o
fn:root($odoc//quantity)
returns $odoc
fn:root($newi)
returns $o
The final three examples could be made type-safe by wrapping their operands with fn:exactly-one().
A sequence
is an ordered collection of zero or more items
.
An item
is either a node or an atomic value. The terms
sequence
and item
are defined formally in
The following functions are defined on sequences.
Function | Meaning |
---|---|
fn:boolean
|
Computes the effective boolean value of the argument sequence. |
op:concatenate
|
Concatenates two sequences. |
fn:index-of
|
Returns a sequence of xs:integer s, each of which is the
index of a member of the sequence specified as the first argument
that is equal to the value of the second argument. If no members of
the specified sequence are equal to the value of the second
argument, the empty sequence is returned. |
fn:empty
|
Indicates whether or not the provided sequence is empty. |
fn:exists
|
Indicates whether or not the provided sequence is not empty. |
fn:distinct-values
|
Returns a sequence in which all but one of a set of duplicate
values, based on value equality, have been deleted. The order in
which the distinct values are returned is |
fn:insert-before
|
Inserts an item or sequence of items at a specified position in a sequence. |
fn:remove
|
Removes an item from a specified position in a sequence. |
fn:reverse
|
Reverses the order of items in a sequence. |
fn:subsequence
|
Returns the subsequence of a given sequence, identified by location. |
fn:unordered
|
Returns the items in the given sequence in a non-deterministic order. |
As in the previous section, for the illustrative examples below, assume an XQuery
or transformation operating on a non-empty Purchase Order document containing a
number of line-item elements. The variable $seq
is bound to the
sequence of line-item nodes in document order. The variables
$item1
, $item2
, etc. are bound to separate, individual
line-item nodes in the sequence.
Summary: Computes the effective boolean value of the sequence
$arg
. See
If $arg
is the empty sequence, fn:boolean
returns false
.
If $arg
is a sequence whose first item is a node, fn:boolean
returns true
.
If $arg
is a singleton value of type xs:boolean
or a derived from xs:boolean
, fn:boolean
returns $arg
.
If $arg
is a singleton value of type xs:string
or a type derived from xs:string
or xdt:untypedAtomic
, fn:boolean
returns false
if the operand value has zero length; otherwise it returns true
.
If $arg
is a singleton value of any numeric type or a type derived from a numeric type, fn:boolean
returns false
if the operand value is NaN
or is numerically equal to zero; otherwise it returns true
.
In all other cases, fn:boolean
raises a type error
The static semantics of this function are described in
The result of this function is not necessarily the same as
. For example, $arg cast as xs:boolean
fn:boolean("false")
returns the
value "true"
whereas "false
" cast as
xs:boolean
returns false
.
let $x := ("a", "b", "c")
fn:boolean($x)
raises a type error
fn:boolean($x[1])
returns true
.
fn:boolean($x[0])
returns false
.
Summary: Returns a sequence consisting of the items in $seq1
followed by the items in $seq2
. This function backs up the
infix operator ",". If either sequence is the empty sequence, the other
operand is returned.
For detailed type semantics, see
op:concatenate((1, 2, 3), (4, 5))
returns (1,
2, 3, 4, 5)
.
op:concatenate((1, 2, 3), ())
returns (1, 2,
3)
.
op:concatenate((), ())
returns ()
.
Summary: Returns a sequence of positive integers giving the positions within
the sequence $seqParam
of items that are equal to $srchParam
.
The collation used by the invocation of this function is determined according
to the rules in
The items in the sequence $seqParam
are compared with
$srchParam
under the rules for the eq
operator.
Values that cannot be compared, i.e. the eq
operator is not
defined for their types, are considered to be distinct. If an item compares
equal, then the position of that item in the sequence
$srchParam
is included in the result.
If the value of $seqParam
is the empty sequence, or if no item
in $seqParam
matches $srchParam
, then the empty
sequence is returned.
The first item in a sequence is at position 1, not position 0.
The result sequence is in ascending numeric order.
fn:index-of ((10, 20, 30, 40), 35)
returns ().
fn:index-of ((10, 20, 30, 30, 20, 10), 20)
returns
(2, 5).
fn:index-of (("a", "sport", "and", "a", "pastime"),
"a")
returns (1, 4).
If @a is an attribute of type xs:NMTOKENS
whose
typed value is
, then: red green blue
fn:index-of (@a, "blue")
returns 3
.
This is because the function calling mechanism atomizes the
attribute node to produce a sequence of three xs:NMTOKEN
s.
Summary: If the value of $arg
is the empty sequence, the
function returns true
; otherwise, the function returns
false
.
fn:empty(fn:remove(("hello", "world"), 1))
returns
false
.
Summary: If the value of $arg
is not the empty sequence, the
function returns true
; otherwise, the function returns
false
.
fn:exists(fn:remove(("hello"), 1))
returns
false
.
Summary: Returns the sequence that results from removing
from $arg
all but one of a set of values that are eq
to one other. Values that cannot be compared, i.e. the eq
operator is not defined for their types, are considered to be distinct.
Values of type xdt:untypedAtomic
are compared as if they were of
type xs:string
. The order in which the sequence of values is
returned is
The static type of the result is a sequence of prime types as defined in
The collation used by the invocation of this function is determined according
to the rules in
If $arg
is the empty sequence, the empty sequence is returned.
For xs:float
and xs:double
values, positive zero
is equal to negative zero and, although NaN
does not equal
itself, if $arg
contains multiple NaN
values a
single NaN
is returned.
If xs:dateTime
, xs:date
or xs:time
values do not have a timezone, they are considered to have the implicit timezone provided by the dynamic context for the purpose of comparison. Note that
xs:dateTime
, xs:date
or xs:time
values
can compare equal even if their timezones are different.
Which value of a set of values that compare equal is returned is
fn:distinct-values((1, 2.0, 3, 2))
might return
(1, 3, 2.0)
.
The following query:xdt:untypedAtomic
.
Summary: Returns a new sequence constructed from the value of
$target
with the value of $inserts
inserted at the
position specified by the value of $position
. (The value of
$target
is not affected by the sequence construction.)
If $target
is the empty sequence, $inserts
is
returned. If $inserts
is the empty sequence,
$target
is returned.
The value returned by the function consists of all items of
$target
whose index is less than $position
,
followed by all items of $inserts
, followed by the remaining
elements of $target
, in that sequence.
If $position
is less than one (1), the first position, the
effective value of $position
is one (1). If
$position
is greater than the number of items in
$target
, then the effective value of $position
is
equal to the number of items in $target
plus 1.
For detailed semantics see,
let $x
:= ("a", "b", "c")
fn:insert-before($x, 0, "z")
returns ("z",
"a", "b", "c")
fn:insert-before($x, 1, "z")
returns ("z",
"a", "b", "c")
fn:insert-before($x, 2, "z")
returns ("a",
"z", "b", "c")
fn:insert-before($x, 3, "z")
returns ("a",
"b", "z", "c")
fn:insert-before($x, 4, "z")
returns ("a",
"b", "c", "z")
Summary: Returns a new sequence constructed from the value of
$target
with the item at the position specified by the value of
$position
removed.
If $position
is less than 1 or greater than the number of items
in $target
, $target
is returned. Otherwise, the
value returned by the function consists of all items of $target
whose index is less than $position
, followed by all items of
$target
whose index is greater than $position
. If
$target
is the empty sequence, the empty sequence is returned.
For detailed type semantics, see
let $x
:= ("a", "b", "c")
fn:remove($x, 0)
returns ("a", "b", "c")
fn:remove($x, 1)
returns ("b", "c")
fn:remove($x, 6)
returns ("a", "b", "c")
fn:remove((), 3)
returns ()
Summary: Reverses the order of items in a sequence. If $arg
is
the empty sequence, the empty sequence is returned.
For detailed type semantics, see
let $x
:= ("a", "b", "c")
fn:reverse($x)
returns ("c", "b", "a")
fn:reverse(("hello"))
returns ("hello")
fn:reverse(())
returns ()
Summary: Returns the contiguous sequence of items in the value of
$sourceSeq
beginning at the position indicated by the value of
$startingLoc
and continuing for the number of items indicated
by the value of $length
.
In the two-argument case, returns:
In the three-argument case, returns:
If $sourceSeq
is the empty sequence, the empty sequence is returned.
If $startingLoc
is zero or negative, the subsequence includes items from the
beginning of the $sourceSeq
.
If $length
is not specified, the subsequence includes items to the end of $sourceSeq
.
If $length
is greater than the number of items in the value of $sourceSeq
following $startingLoc
, the subsequence includes items to the end of $sourceSeq
.
The first item of a sequence is located at position 1, not position 0.
For detailed type semantics, see
The reason the function accepts arguments of type xs:double
is that many computations on untyped data return an xs:double
result; and the reason for the rounding rules is to compensate for any imprecision in these floating-point computations.
Assume $seq = ($item1, $item2, $item3, $item4, ...)
fn:subsequence($seq, 4)
returns ($item4, ...)
fn:subsequence($seq, 3, 2)
returns ($item3, $item4)
Summary: Returns the items of $sourceSeq
in an
Query optimizers may be able to do a better job if the order of the output sequence is not specified. For example, when retrieving prices from a purchase order, if an index exists on prices, it may be more efficient to return the prices in index order rather than in document order.
The following functions test the cardinality of their sequence arguments.
Function | Meaning |
---|---|
fn:zero-or-one
|
Returns the input sequence if it contains zero or one items. Raises an error otherwise. |
fn:one-or-more
|
Returns the input sequence if it contains one or more items. Raises an error otherwise. |
fn:exactly-one
|
Returns the input sequence if it contains exactly one item. Raises an error otherwise. |
The functions fn:zero-or-one
, fn:one-or-more
, and
fn:exactly-one
defined in this section, check that the cardinality
of a sequence is in the expected range. They are particularly useful with regard
to static typing. For example, the XML Schema fn:one-or-more
at the appropriate place will provide a
suitable static type at query analysis time, and confirm that the length is
correct with a dynamic check at query execution time.
Summary: Returns $arg
if it contains zero or one items.
Otherwise, raises an error
For detailed type semantics, see
Summary: Returns $arg
if it contains one or more items.
Otherwise, raises an error
For detailed type semantics, see
Summary: Returns $arg
if it contains exactly one item. Otherwise,
raises an error
For detailed type semantics, see
Function | Meaning |
---|---|
fn:deep-equal
|
Returns true if the two arguments have items that
compare equal in corresponding positions. |
op:union
|
Returns the union of the two sequence arguments, eliminating duplicates. |
op:intersect
|
Returns the intersection of the two sequence arguments, eliminating duplicates. |
op:except
|
Returns the difference of the two sequence arguments, eliminating duplicates. |
As in the previous sections, for the illustrative examples below, assume an
XQuery or transformation operating on a Purchase Order document containing a
number of line-item elements. The variables $item1
,
$item2
, etc. are bound to individual line-item nodes in the
sequence. We use sequences of these nodes in some of the examples below.
Summary: This function assesses whether two sequences are deep-equal to each
other. To be deep-equal, they must contain items that are pair wise
deep-equal; and for two items to be deep-equal, they must either be atomic
values that compare equal, or nodes of the same kind, with the same name,
whose children are deep-equal. This is defined in more detail below. The
$collation
argument identifies a collation which is used at all
levels of recursion when strings are compared (but not when names are
compared), according to the rules in
If the two sequences are both empty, the function returns true
.
If the two sequences are of different lengths, the function returns false
.
If the two sequences are of the same length, the function returns
true
if and only if every item in the sequence
$parameter1
is deep-equal to the item at the same position in
the sequence $parameter2
. The rules for deciding whether two
items are deep-equal follow.
Call the two items $i1
and $i2
respectively.
If $i1
and $i2
are both atomic values, they are
deep-equal if and only if ($i1 eq $i2)
is true
. Or if both values are NaN
.
If the eq
operator is not defined for $i1
and
$i2
, the function returns false
.
If one of the pair $i1
or $i2
is an atomic value
and the other is a node, the function returns false
.
If $i1
and $i2
are both nodes, they are compared as
described below:
If the two nodes are of different kinds, the result is false
.
If the two nodes are both document nodes then they are deep-equal if and only
if the sequence $i1/(*|text())
is deep-equal to the sequence $i2/(*|text())
.
If the two nodes are both element nodes then they are deep-equal if and only if all of the following conditions are satisfied:
the two nodes have the same name, that is (node-name($i1) eq node-name($i2))
.
the two nodes are both annotated as having simple content or both nodes are annotated as having complex content.
the two nodes have the same number of attributes, and for every
attribute $a1
in $i1/@*
there exists an
attribute $a2
in $i2/@*
such that
$a1
and $a2
are deep-equal.
One of the following conditions holds:
Both element nodes have a type annotation that is simple content, and the
typed value of $i1
is deep-equal to the typed
value of $i2
.
Both element nodes have a type annotation that
is complex content with elementOnly content, and each child element of $i1
is deep-equal to the corresponding child element of $i2
.
Both element nodes have a type annotation that
is complex content with mixed content, and the sequence $i1/(*|text())
is
deep-equal to the sequence $i2/(*|text())
.
Both element nodes have a type annotation that is complex content with empty content.
If the two nodes are both attribute nodes then they are deep-equal if and only if both the following conditions are satisfied:
the two nodes have the same name, that is (node-name($i1) eq node-name($i2))
.
the typed value of $i1
is deep-equal to the typed value of $i2
.
If the two nodes are both processing instruction nodes or namespace bindings, then they are deep-equal if and only if both the following conditions are satisfied:
the two nodes have the same name, that is (node-name($i1) eq node-name($i2))
.
the string value of $i1
is equal to the string value of $i2
.
If the two nodes are both text nodes or comment nodes, then they are deep-equal if and only if their string-values are equal.
The two nodes are not required to have the same type annotation, and
they are not required to have the same in-scope namespaces. They may
also differ in their parent, their base URI, and the values returned by the is-id
and is-idrefs
accessors (see
The contents of comments and processing instructions are significant only if these nodes appear directly as items in the two sequences being compared. The content of a comment or processing instruction that appears as a descendant of an item in one of the sequences being compared does not affect the result. However, the presence of a comment or processing instruction, if it causes a text node to be split into two text nodes, may affect the result.
The result of fn:deep-equal(1, current-dateTime())
is
false
; it does not raise an error.
fn:deep-equal($at, $at/*)
returns false
.
fn:deep-equal($at/name[1], $at/name[2])
returns false
.
fn:deep-equal($at/name[1], $at/name[3])
returns true
.
fn:deep-equal($at/name[1], 'Peter Parker')
returns false
.
Summary: Constructs a sequence containing every node that occurs in the
values of either $parameter1
or $parameter2
,
eliminating duplicate nodes. Nodes are returned in document order. Two nodes
are duplicates if they are op:is-same-node()
.
If either operand is the empty sequence, a sequence is returned containing the nodes in the other operand in document order after eliminating duplicates.
For detailed type semantics, see
This function backs up the "union" or "|" operator.
Assume $seq1 = ($item1, $item2), $seq2 = ($item1, $item2)
and $seq3 = ($item2, $item3)
.
op:union($seq1, $seq1)
returns the sequence
($item1, $item2)
.
op:union($seq2, $seq3)
returns the sequence
consisting of ($item1, $item2, $item3)
.
Summary: Constructs a sequence containing every node that occurs in the
values of both $parameter1
and $parameter2
,
eliminating duplicate nodes. Nodes are returned in document order.
If either operand is the empty sequence, the empty sequence is returned.
Two nodes are duplicates if they are op:is-same-node()
.
For detailed type semantics, see
This function backs up the "intersect" operator.
Assume $seq1 = ($item1, $item2), $seq2 = ($item1, $item2)
and $seq3 = ($item2, $item3)
.
op:intersect($seq1, $seq1)
returns the sequence
($item1, $item2)
.
op:intersect($seq2, $seq3)
returns the sequence
($item2)
.
Summary: Constructs a sequence containing every node that occurs in the value
of $parameter1
, but not in the value of
$parameter2
, eliminating duplicate nodes. Nodes are returned in
document order.
If $parameter1
is the empty sequence, the empty sequence is
returned. If $parameter2
is the empty sequence, a sequence is
returned containing the nodes in $parameter1
in document order
after eliminating duplicates.
Two nodes are duplicates if they are op:is-same-node()
.
For detailed type semantics, see
This function backs up the "except" operator.
Assume $seq1 = ($item1, $item2), $seq2 = ($item1, $item2)
and $seq3 = ($item2, $item3)
.
op:except($seq1, $seq2)
returns the empty sequence.
op:except($seq2, $seq3)
returns the sequence
($item1)
.
Aggregate functions take a sequence as argument and return a single value
computed from values in the sequence. Except for fn:count
, the
sequence must consist of values of a single type or one if its subtypes, or they
must be numeric. xdt:untypedAtomic
values are permitted in the
input sequence and handled by special conversion rules. The type of the items in
the sequence must also support certain operations.
Function | Meaning |
---|---|
fn:count
|
Returns the number of items in a sequence. |
fn:avg
|
Returns the average of a sequence of values. |
fn:max
|
Returns the maximum value from a sequence of comparable values. |
fn:min
|
Returns the minimum value from a sequence of comparable values. |
fn:sum
|
Returns the sum of a sequence of values. |
Summary: Returns the number of items in the value of $arg
.
Returns 0 if $arg
is the empty sequence.
Assume $seq1 = ($item1, $item2)
and $seq3 = ()
,
the empty sequence.
fn:count($seq1)
returns 2
.
fn:count($seq3)
returns 0
.
Assume $seq2 = (98.5, 98.3, 98.9)
.
fn:count($seq2)
returns 3
.
fn:count($seq2[. > 100])
returns 0
.
Summary: Returns the average of the values in the input
sequence $arg
, that is, the sum of the values divided by the
number of values.
If $arg
is the empty sequence, the empty sequence is returned.
If $arg
contains values of type xdt:untypedAtomic
they are cast to xs:double
.
Duration values must either all be xdt:yearMonthDuration
values
or must all be xdt:dayTimeDuration
values. For numeric values,
the numeric promotion rules defined in $arg
must contain items of a single type, which must be one of
the four numeric types, xdt:yearMonthDuration
or
xdt:dayTimeDuration
or one if its subtypes.
If the above conditions are not met, then a type error is raised
Otherwise, returns the average of the values computed as sum($arg) div
count($arg)
.
For detailed type semantics, see
Assume $d1 = xdt:yearMonthDuration("P20Y")
and $d2 =
xdt:yearMonthDuration("P10M")
and $seq3 = (3, 4, 5)
.
fn:avg($seq3)
returns 4.0
.
fn:avg(($d1, $d2))
returns a
yearMonthDuration
with value 125
months.
fn:avg(($d1, $seq3))
raises a type error
fn:avg(())
returns ()
.
fn:avg((xs:float('INF')), xs:float('-INF'))
returns
NaN
.
fn:avg(($seq3, xs:float('NaN'))
returns
NaN
.
Summary: Selects an item from the input sequence $arg
whose
value is greater than or equal to the value of every other item in the input
sequence. If there are two or more such items, then the specific item whose
value is returned is
The following rules are applied to the input sequence:
Values of type xdt:untypedAtomic
in $arg
are cast to xs:double
.
For numeric values,
the numeric promotion rules defined in
The items in the resulting sequence may be reordered in an arbitrary order. The resulting sequence is referred to below as the converted sequence. This function returns an item from the converted sequence rather than the input sequence.
If the converted sequence is empty, the empty sequence is returned.
All items in $arg
must be numeric or derived from a single base
type for which the ge
operator is defined. In addition, the values in
the sequence must have a total order. If date/time values do not have a
timezone, they are considered to have the implicit timezone provided by the dynamic context for purposes of comparison. Duration values
must either all be xdt:yearMonthDuration
values or must all be
xdt:dayTimeDuration
values.
If any of these conditions is not met, then a type error is raised
If the converted sequence contains the value NaN
, the value
NaN
is returned.
If the items in the value of $arg
are of type
xs:string
or types derived by restriction from
xs:string
, then the determination of the item with the largest
value is made according to the collation that is used. If the type of the
items in $arg
is not xs:string
and
$collation
is specified, the collation is ignored.
The collation used by the invocation of this function is determined according
to the rules in
Otherwise, the result of the function is the result of the expression:
evaluated with $collation
as the default collation if specified, and with $c
as the converted sequence.
For detailed type semantics, see
If the converted sequence contains exactly one value then that value is returned.
The default type when the fn:max
function is applied
to xdt:untypedAtomic
values is xs:double
. This
differs from the default type for operators such as gt
, and
for sorting in XQuery and XSLT, which is xs:string
.
fn:max((3,4,5))
returns 5
.
fn:max((5, 5.0e0))
returns 5.0e0
.
fn:max((3,4,"Zero"))
raises a type error
fn:max((fn:current-date(), xs:date("2001-01-01")))
typically returns the current date.
fn:max(("a", "b", "c"))
returns "c" under a typical
default collation.
Summary: selects an item from the input sequence $arg
whose
value is less than or equal to the value of every other item in the input
sequence. If there are two or more such items, then the specific item whose
value is returned is
The following rules are applied to the input sequence:
Values of type xdt:untypedAtomic
in $arg
are cast to xs:double
.
For numeric values,
the numeric promotion rules defined in
The items in the resulting sequence may be reordered in an arbitrary order. The resulting sequence is referred to below as the converted sequence. This function returns an item from the converted sequence rather than the input sequence.
If the converted sequence is empty, the empty sequence is returned.
All items in $arg
must be numeric or derived from a single base
type for which the le
operator is defined. In addition, the values in
the sequence must have a total order. If date/time values do not have a
timezone, they are considered to have the implicit timezone provided by the dynamic context for the purpose of comparison. Duration values
must either all be xdt:yearMonthDuration
values or must all be
xdt:dayTimeDuration
values.
If any of these conditions is not met, a type error is raised
If the converted sequence contains the value NaN
, the value
NaN
is returned.
If the items in the value of $arg
are of type
xs:string
or types derived by restriction from
xs:string
, then the determination of the item with the smallest
value is made according to the collation that is used. If the type of the
items in $arg
is not xs:string
and
$collation
is specified, the collation is ignored.
The collation used by the invocation of this function is determined according
to the rules in
Otherwise, the result of the function is the result of the expression:
evaluated with $collation
as the default collation if specified, and with $c
as the converted sequence.
For detailed type semantics, see
If the converted sequence contains exactly one value then that value is returned.
The default type when the fn:min
function is applied
to xdt:untypedAtomic
values is xs:double
. This
differs from the default type for operators such as lt
, and
for sorting in XQuery and XSLT, which is xs:string
.
fn:min((3,4,5))
returns 3
.
fn:min((5, 5.0e0))
returns 5.0e0
.
fn:min((3,4,"Zero"))
raises a type error
fn:min(xs:float(0.0E0), xs:float(-0.0E0)
can return either positive or negative zero.
fn:min((fn:current-date(), xs:date("2001-01-01")))
typically returns xs:date("2001-01-01")
.
fn:min(("a", "b", "c"))
returns "a" under a typical
default collation.
Summary: Returns a value obtained by adding together the values
in $arg
. If $zero
is not specified, then the value
returned for an empty sequence is the xs:integer
value 0. If
$zero
is specified, then the value returned for an empty
sequence is $zero.
.
Any values of type xdt:untypedAtomic
in $arg
are
cast to xs:double
. The items in the resulting sequence may be
reordered in an arbitrary order. The resulting sequence is referred to below
as the converted sequence.
If the converted sequence is empty, then the single-argument form of the
function returns the xs:integer
value 0
; the
two-argument form returns the value of the argument $zero
.
If the converted sequence contains the value NaN
,
NaN
is returned.
All items in $arg
must be numeric or derived from a single base
type. In addition, the type must support addition. Duration values must
either all be xdt:yearMonthDuration
values or must all be
xdt:dayTimeDuration
values. For numeric values, the numeric
promotion rules defined in
If the above conditions are not met, a type error is raised
Otherwise, the result of the function, using the second signature, is the result of the expression:
where $c
is the converted sequence.
The result of the function, using the first signature, is the result of the
expression: fn:sum($arg, 0)
.
For detailed type semantics, see
The second argument allows an appropriate value to be defined to represent the sum of an empty sequence. For example, when summing a sequence of durations it would be appropriate to return a zero-length duration of the appropriate type. This argument is necessary because a system that does dynamic typing cannot distinguish "an empty sequence of integers", for example, from "an empty sequence of durations".
If the converted sequence contains exactly one value then that value is returned.
Assume:
fn:sum(($d1, $d2))
returns an
xdt:yearMonthDuration
with a value of
250
months.
fn:sum($seq1[. < xdt:yearMonthDuration('P3M')],
xdt:yearMonthDuration('P0M'))
returns an
xdt:yearMonthDuration
with a value of
0
months.
fn:sum($seq3)
returns 12
.
fn:sum(())
returns 0
.
fn:sum((),())
returns ()
.
fn:sum((1 to 100)[.<0], 0)
returns 0
.
fn:sum(($d1, 9E1))
raises an error
Function | Meaning |
---|---|
op:to
|
Returns the sequence containing every xs:integer
between the values of the operands. |
fn:id
|
Returns the sequence of element nodes having an ID value matching the one or more of the supplied IDREF values. |
fn:idref
|
Returns the sequence of element or attribute nodes with an IDREF value matching one or more of the supplied ID values. |
fn:doc
|
Returns a document node retrieved using the specified URI. |
fn:doc-available
|
Returns true if a document node can be retrieved using
the specified URI. |
fn:collection
|
Returns a sequence of nodes retrieved using the specified URI or the nodes in the default collection. |
Summary: Returns the sequence containing every xs:integer
whose
value is between the value of $firstval
(inclusive) and the
value of $lastval
(inclusive), in monotonic order. If the value
of the first operand is greater than the value of the second, the empty
sequence is returned. If the values of the two operands are equal, a
sequence containing a single xs:integer
equal to the value is returned.
This function backs up the "to" operator.
1 to 3
returns (1, 2, 3)
3 to 1
returns ()
5 to 5
returns 5
Summary: Returns the sequence of element nodes that have an ID
value matching the value of one or more of the IDREF
values
supplied in $arg
.
The function returns a sequence, in document order with duplicates
eliminated, containing every element node E
that satisfies all
the following conditions:
E
is in the target document. The target document is the
document containing $node
, or the document containing
the context node if the second argument is omitted. An error is
raised $node
, or the context item if the second argument is
omitted, is a node in a tree whose root is not a document node or if
the second argument is omitted and there is no context item
E
has an ID
value equal to one of the
candidate IDREF
values, where:
An element has an ID
value equal to
V
if either or both of the following conditions
are true:
The is-id
property (See eq
operator using the Unicode code point collation (http://www.w3.org/2005/xpath-functions/collation/codepoint
).
The element has an attribute node whose
is-id
property (See V
under the rules of the
eq
operator using the Unicode code
point collation (http://www.w3.org/2005/xpath-functions/collation/codepoint
).
Each xs:string
in $arg
is parsed
as if it were of type IDREFS
, that is, each
xs:string
in $arg
is treated as a
space-separated sequence of tokens, each acting as an
IDREF
. These tokens are then included in the
list of candidate IDREF
s. If any of the tokens
is not a lexically valid IDREF
(that is, if it
is not lexically an xs:NCName
), it is ignored.
Formally, The candidate IDREF
values are the
strings in the sequence given by the expression:
If several elements have the same ID
value, then
E
is the one that is first in document order.
If the data model is constructed from an Infoset, an attribute will have
the is-id
property if the corresponding attribute in the
Infoset had an attribute type of ID
: typically this means
the attribute was declared as an ID
in a DTD.
If the data model is constructed from a PSVI, an element or attribute
will have the is-id
property if its schema-defined type
is xs:ID
or a type derived by restriction from xs:ID
.
No error is raised in respect of a candidate IDREF
value
that does not match the ID
of any element in the document.
If no candidate IDREF
value matches the ID
value of any element, the function returns the empty sequence.
It is not necessary that the supplied argument should have type xs:IDREF
or xs:IDREFS
, or that it should be
derived from a node with the is-idrefs
property.
An element may have more than one ID
value. This can occur
with synthetic data models or with data models constructed from a PSVI
where an the element and one of its attributes are both typed as xs:ID
.
If the source document is well-formed but not valid, it is possible for
two or more elements to have the same ID
value. In this
situation, the function will select the first such element.
It is also possible in a well-formed but invalid document to have an
element or attribute that has the is-id property but whose value does
not conform to the lexical rules for the xs:ID
type. Such a
node will never be selected by this function.
Summary: Returns the sequence of element or attribute nodes with an
IDREF
value matching the value of one or more of
the ID
values supplied in $arg
.
The function returns a sequence, in document order with duplicates
eliminated, containing every element or attribute node $N
that
satisfies all the following conditions:
$N
is in the target document. The target document is
the document containing $node
, or the document
containing the context node if the second argument is omitted. An
error is raised $node
, or the context item if the second argument is
omitted, is a node in a tree whose root is not a document node or if
the second argument is omitted and there is no context item
$N
has an IDREF
value equal to one of the
candidate ID
values, where:
A node $N
has an IDREF
value equal
to V
if both of the following conditions are true:
The is-idrefs
property (See $N
is true
The sequence V
under the rules of the
eq
operator using the Unicode code
point collation (http://www.w3.org/2005/xpath-functions/collation/codepoint
).
Each xs:string
in $arg
is parsed
as if it were of lexically of type xs:ID
. These
xs:string
s are then included in the list of
candidate xs:ID
s. If any of the strings in
$arg
is not a lexically valid
xs:ID
(that is, if it is not lexically an
xs:NCName
), it is ignored. More formally, the
candidate ID
values are the strings in the
sequence
An element or attribute typically acquires the is-idrefs
property by being validated against the schema type
xs:IDREF
or xs:IDREFS
, or (for attributes only)
by being described as of type IDREF
or IDREFS
in a DTD.
No error is raised in respect of a candidate ID
value that
does not match the IDREF
value of any element or attribute
in the document. If no candidate ID
value matches the
IDREF
value of any element or attribute, the function
returns the empty sequence.
It is possible for two or more nodes to have an IDREF
value
that matches a given candidate ID
value. In this situation,
the function will return all such nodes. However, each matching node
will be returned at most once, regardless how many candidate
ID
values it matches.
It is possible in a well-formed but invalid document to have a node
whose is-idrefs
property is true but that does not conform
to the lexical rules for the xs:IDREF
type. The effect of
the above rules is that ill-formed candidate ID
values and
ill-formed IDREF
values are ignored.
Summary: Retrieves a document using an xs:anyURI
, which may
include a fragment identifier, supplied as an xs:string
. If
$uri
is not a valid xs:anyURI
, an error is raised
xs:string
. If the
If $uri
is the empty sequence, the result is an empty sequence.
This function is
For detailed type semantics, see
If $uri
is read from a source document, it is generally
appropriate to resolve it relative to the base URI property of the
relevant node in the source document. This can be achieved by calling
the fn:resolve-uri
function, and passing the resulting
absolute URI as an argument to the fn:doc
function.
If two calls to this function supply different absolute URI References as arguments, the same document node may be returned if the implementation can determine that the two arguments refer to the same resource.
By defining the semantics of this function in terms of a
string-to-document-node mapping in the dynamic context, the specification is
acknowledging that the results of this function are outside the purview of
the language specification itself, and depend entirely on the run-time
environment in which the expression is evaluated. This run-time environment
includes not only an unpredictable collection of resources ("the web"), but
configurable machinery for locating resources and turning their contents
into document nodes within the XPath data model. Both the set of resources
that are reachable, and the mechanisms by which those resources are parsed
and validated, are
One possible processing model for this function is as follows. The resource
identified by the URI Reference is retrieved. If the resource cannot be
retrieved, an error is raised
Various aspects of this processing are
The set of URI schemes that the implementation recognizes is implementation-defined. Implementations may allow the mapping of URIs to resources to be configured by the user, using mechanisms such as catalogs or user-written URI handlers.
The handling of non-XML media types is implementation-defined. Implementations may allow instances of the data model to be constructed from non-XML resources, under user control.
It is
Implementations may provide user-defined error handling options that allow processing to continue following an error in retrieving a resource, or in parsing and validating its content. When errors have been handled in this way, the function may return either an empty sequence, or a fallback document provided by the error handler.
Summary: If fn:doc($uri)
returns a document node, this function
returns true
. If $uri
is not a valid
xs:anyURI
, an error is raised false
.
If this function returns true
, then
calling fn:doc($uri)
within the same
Summary: This function takes an xs:string
as argument and
returns a sequence of nodes obtained by interpreting $arg
as an
xs:anyURI
and resolving it according to the mapping specified
in $arg
is not specified, the function returns
the sequence of the nodes in the default collection in the dynamic context.
See
If the $arg
is a relative xs:anyURI
, it is
resolved against the value of the base-URI property from the static context.
If $arg
is not a valid xs:anyURI
, an error is raised
If $arg
is the empty sequence, the function behaves as if it had
been called without an argument. See above.
This function is
This function provides a facility for users to work with a collection of
documents which may be contained in a directory or rows of a Relational
table or other implementation-specific construct. An implementation may
also use external variables to identify external resources, but
fn:collection()
provides functionality not provided by
external variables. Specifying resources using URIs is useful because
URIs are dynamic, can be parameterized, and do not rely on an external environment.
The following functions are defined to obtain information from the dynamic context.
Function | Meaning |
---|---|
fn:position
|
Returns the position of the context item within the sequence of items currently being processed. |
fn:last
|
Returns the number of items in the sequence of items currently being processed. |
fn:current-dateTime
|
Returns the current xs:dateTime . |
fn:current-date
|
Returns the current xs:date . |
fn:current-time
|
Returns the current xs:time . |
fn:implicit-timezone
|
Returns the value of the implicit timezone property from the dynamic context. |
fn:default-collation
|
Returns the value of the default collation property from the static context. |
fn:static-base-uri
|
Returns the value of the base-uri property from the static context. |
Summary: Returns the context position from the dynamic context.
(See
Summary: Returns the context size from the dynamic context.
(See
Summary: Returns the current dateTime (with timezone) from the dynamic context.
(See xs:dateTime
that is current at some time during the
evaluation of a query or transformation in
which fn:current-dateTime()
is executed. This function is fn:current-dateTime()
is
fn:current-dateTime()
returns an
xs:dateTime
corresponding to the current date and time.
For example, an invocation of fn:current-dateTime()
might return 2004-05-12T18:17:15.125Z
corresponding to
the current time on May 12, 2004 in timezone Z
.
Summary: Returns xs:date(fn:current-dateTime())
. This is an
xs:date
(with timezone) that is current at some time during the
evaluation of a query or transformation in which fn:current-date()
is executed. This function is fn:current-date()
is
fn:current-date()
returns an xs:date
corresponding to the current date and time. For example, an
invocation of fn:current-date()
might return
2004-05-12+01:00
.
Summary: Returns xs:time(fn:current-dateTime())
. This is an
xs:time
(with timezone) that is current at some time during the
evaluation of a query or transformation in which fn:current-time()
is executed. This function is fn:current-time()
is
fn:current-time()
returns an xs:time
corresponding to the current date and time. For example, an
invocation of fn:current-time()
might return
23:17:00.000-05:00
.
Summary: Returns the value of the implicit timezone property from the dynamic
context. Components of the dynamic context are discussed in
Summary: Returns the value of the default collation property from the static
context. Components of the static context are discussed in
The default collation property can never be undefined. If it is not
explicitly defined, a system defined default can be invoked. If this is not
provided, the Unicode code point collation
(http://www.w3.org/2005/xpath-functions/collation/codepoint
)
is used.
Summary: Returns the value of the base-uri property from the static context. If
the base-uri property is undefined, the empty sequence is returned. Components
of the static context are discussed in
Constructor functions and cast expressions accept an expression and return a value
of a given type. They both convert a source value,
means exactly the same as xs:date("2003-01-01")
."2003-01-01"
cast as
xs:date?
The cast expression takes a type name to indicate the target type of the conversion.
See
Where the argument to a cast is a literal, the result of the function may be evaluated statically; if an error is encountered during such evaluation, it may be reported as a static error.
This section defines casting between the 19 primitive types defined in xdt:untypedAtomic
,
xs:integer
and the two derived types of
xs:duration
(xdt:yearMonthDuration
and xdt:dayTimeDuration
). These four types are not primitive types
but they are treated as primitive types in this section. The type conversions
that are supported are indicated in the table below. In this table, there is a
row for each primitive type with that type as the source of the conversion and
there is a column for each primitive type as the target of the conversion. The
intersections of rows and columns contain one of three characters:
Y
indicates that a conversion from values of the type to which
the row applies to the type to which the column applies is supported;
N
indicates that there are no supported conversions from values
of the type to which the row applies to the type to which the column applies;
and M
indicates that a conversion from values of the type to
which the row applies to the type to which the column applies may succeed for
some values in the value space and fails for others.
xs:NOTATION
as an abstract type.
Thus, casting to xs:NOTATION
from any other type including xs:NOTATION
is not permitted. However, casting from one subtype of xs:NOTATION
to another subtype of xs:NOTATION
is permitted.
Casting is not supported to or from xs:anySimpleType
. Thus, there is
no row or column for this type in the table below. For any node that has not
been validated or has been validated as xs:anySimpleType
, the typed
value of the node is an atomic value of type xdt:untypedAtomic
.
There are no atomic values with the type annotation xs:anySimpleType
at runtime.
Similarly, casting is not supported to or from xs:anyAtomicType
. There are no atomic values with the type annotation xs:anyAtomicType
at runtime, although this can be a statically inferred type.
An attempt to cast to any of the above three type raises a static error
If casting is attempted from an
In the following table, the columns and rows are identified by short codes that identify simple types as follows:
In the following table, the notation S\T
indicates that the source
(S
) of the conversion is indicated in the column below the
notation and that the target (T
) is indicated in the row to the
right of the notation.
S\T | uA | str | flt | dbl | dec | int | dur | yMD | dTD | dT | tim | dat | gYM | gYr | gMD | gDay | gMon | bool | b64 | hxB | aURI | QN | NOT |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
uA | Y | Y | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | N | N |
str | Y | Y | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M | M |
flt | Y | Y | Y | Y | M | M | N | N | N | N | N | N | N | N | N | N | N | Y | N | N | N | N | N |
dbl | Y | Y | Y | Y | M | M | N | N | N | N | N | N | N | N | N | N | N | Y | N | N | N | N | N |
dec | Y | Y | Y | Y | Y | Y | N | N | N | N | N | N | N | N | N | N | N | Y | N | N | N | N | N |
int | Y | Y | Y | Y | Y | Y | N | N | N | N | N | N | N | N | N | N | N | Y | N | N | N | N | N |
dur | Y | Y | N | N | N | N | Y | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | N | N |
yMD | Y | Y | N | N | N | N | Y | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | N | N |
dTD | Y | Y | N | N | N | N | Y | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | N | N |
dT | Y | Y | N | N | N | N | N | N | N | Y | Y | Y | Y | Y | Y | Y | Y | N | N | N | N | N | N |
tim | Y | Y | N | N | N | N | N | N | N | N | Y | N | N | N | N | N | N | N | N | N | N | N | N |
dat | Y | Y | N | N | N | N | N | N | N | Y | N | Y | Y | Y | Y | Y | Y | N | N | N | N | N | N |
gYM | Y | Y | N | N | N | N | N | N | N | N | N | N | Y | N | N | N | N | N | N | N | N | N | N |
gYr | Y | Y | N | N | N | N | N | N | N | N | N | N | N | Y | N | N | N | N | N | N | N | N | N |
gMD | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | Y | N | N | N | N | N | N | N | N |
gDay | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | N | Y | N | N | N | N | N | N | N |
gMon | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | N | N | Y | N | N | N | N | N | N |
bool | Y | Y | Y | Y | Y | Y | N | N | N | N | N | N | N | N | N | N | N | Y | N | N | N | N | N |
b64 | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | Y | Y | N | N | N |
hxB | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | Y | Y | N | N | N |
aURI | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | Y | N | N |
QN | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | Y | N |
NOT | Y | Y | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | M |
The following sub-sections define the semantics of casting from a primitive type
to a primitive type. Semantics of casting to and from a derived type are defined
in sections
When the supplied value is an instance of xs:string
or an
instance of xdt:untypedAtomic
, it is treated as being a string
value and mapped to a typed value of the target type as defined in "13" cast as xs:unsignedInt
returns the xs:unsignedInt
typed
value 13
. This could also be written xs:unsignedInt("13")
. If the cast fails, error
When casting from xs:string
or xdt:untypedAtomic
to a derived type where the derived type is restricted by a pattern facet, the
lexical form is first checked against the pattern before further casting is attempted (See
In casting to numerics, if the value is too large or small to be accurately represented by the implementation, it is handled as an overflow or underflow as defined in
Casting is permitted from xs:string
and
xdt:untypedAtomic
to any primitive atomic type or any atomic
type derived by restriction, except xs:QName
or xs:NOTATION
.
Casting is permitted to xs:QName
and types derived from xs:NOTATION
only from xs:string
literals.
Casting to xs:NOTATION
is not permitted because it is an abstract type. A
static error is raised xs:QName
or a type derived from xs:QName
or xs:NOTATION
is not an xs:string
literal.
For xs:anyURI
, the extent to which an implementation validates the
lexical form of xs:anyURI
is
Casting is permitted from any primitive type to the primitive types
xs:string
and xdt:untypedAtomic
.
When a value of any simple type is cast as xs:string
, the
derivation of the xs:string
value
If xs:string
or a type derived from
xs:string
,
If xs:anyURI
, the type conversion is
performed without escaping any characters.
If xs:QName
,
fn:concat(fn:prefix-from-QName(
SV
":",
fn:local-name-from-QName(
SV
))
.
If
If xs:integer
,
If xs:decimal
, then:
If xs:integer
, that is, if there are no
significant digits after the decimal point, then the
value is converted from an xs:decimal
to an xs:integer
and the resulting
xs:integer
is converted to an
xs:string
using the rule above.
Otherwise, the canonical lexical representation of
If xs:float
or
xs:double
, then:
If xs:decimal
and the
resulting xs:decimal
is converted to an
xs:string
according to the rules above, as though using an
implementation of xs:decimal
that imposes no limits on the
totalDigits
or
fractionDigits
facets.
If
Otherwise, the canonical lexical representation of
xs:float
and
xs:double
is a mantissa, which is a
xs:decimal
, followed by the letter "E",
followed by an exponent which is
an xs:integer
. Leading zeroes and the
preceding optional "+" sign are prohibited in the
exponent. If the exponent is zero it must be
indicated by "E0". For the mantissa, the preceding
optional "+" sign is prohibited and the decimal
point is required. Leading and trailing zeroes are
prohibited subject to the following: number
representations must be normalized such that there
is a single digit which is non-zero to the left of
the decimal point and at least a single digit to the
right of the decimal point unless the value being
represented is zero. Beyond the one required digit
after the decimal point in the mantissa, there must
be as many, but only as many, additional digits as
are needed to uniquely distinguish the value from
all other values for the datatype after rounding the
final digit.
The above wording has been accepted by the XML
Schema Working Group for the canonical form of
the xs:float
and xs:double
datatypes. When this
wording appears in a publicly available
document the paragraph above will be replaced by
an appropriate reference.
If xs:dateTime
, xs:date
or xs:time
, xs:string
using the functions described in year
component is cast to xs:string
using eg:convertYearToString
. The month
, day
, hour
and minute
components are cast to xs:string
using eg:convertTo2CharString
. The second
component is cast to xs:string
using eg:convertSecondsToString
. The timezone component, if present, is cast to xs:string
using eg:convertTZtoString
.
Note that the hours component of the resulting string
will never be "24"
. Midnight is always represented as "00:00:00"
.
If xdt:yearMonthDuration
or xdt:dayTimeDuration
,
If xs:duration
then let SV
cast as xdt:yearMonthDuration
, and let SV
cast as xdt:dayTimeDuration
; Now, let the next intermediate value, SYM
cast as
TT
SDT
cast as
TT
If
Otherwise,
In all other cases,
To cast as xdt:untypedAtomic
the value is cast as
xs:string
, as described above, and the type annotation changed
to xdt:untypedAtomic
.
The string representations of numeric values are backwards compatible
with XPath 1.0 except for the special values positive and negative
infinity, negative zero and values outside the range 1.0e-6
to 1.0e+6
.
When a value of any simple type is cast as xs:float
, the xs:float
If xs:float
, then
If xs:double
, then
if xs:double
value
INF
, -INF
, NaN
,
positive zero, or negative zero, then xs:float
value INF
,
-INF
, NaN
, positive zero, or
negative zero respectively.
otherwise, m × 2^e
where the mantissa
m
and exponent e
are signed
xs:integer
s whose value range is defined in
if m
(the mantissa of
xs:float
value (-2^24+1 to +2^24-1)
, then it
is divided by 2^N
where
N
is the lowest positive
xs:integer
that brings the result
of the division within the permitted range, and
the exponent e
is increased by
N
. This is integer division (in
effect, the binary value of the mantissa is
truncated on the right). Let M
be
the mantissa and E
the exponent
after this adjustment.
if E
exceeds 104
(the
maximum exponent value in the value space of
xs:float
) then xs:float
value INF
or -INF
depending on the sign of M
.
if E
is less than -149
(the minimum exponent value in the value space
of xs:float
) then xs:float
value positive or
negative zero depending on the sign of M
otherwise, xs:float
value M × 2^E
.
If xs:decimal
, or
xs:integer
, then xs:float(
cast as xs:string)
and the conversion is complete.
If xs:boolean
, 1.0E0
if true
and to 0.0E0
if false
and the conversion is complete.
If xdt:untypedAtomic
or xs:string
, see
Implementations "-0.0E0" cast as xs:float
.
When a value of any simple type is cast as xs:double
, the
xs:double
value
If xs:double
, then
If xs:float
or a type derived
from xs:float
, then
if xs:float
value
INF
, -INF
, NaN
,
positive zero, or negative zero, then xs:double
value INF
,
-INF
, NaN
, positive zero, or
negative zero respectively.
otherwise, m × 2^e
where the
mantissa m
and exponent e
are
signed xs:integer
values whose value range
is defined in xs:double
value
m × 2^e
.
If xs:decimal
or
xs:integer
, then xs:double(
cast as xs:string)
and the conversion is complete.
If xs:boolean
, 1.0E0
if true
and to 0.0E0
if false
and the conversion is complete.
If xdt:untypedAtomic
or xs:string
, see
Implementations "-0.0E0" cast as xs:double
.
When a value of any simple type is cast as xs:decimal
, the
xs:decimal
value
If xs:decimal
,
xs:integer
or a type derived from them, then
xs:decimal
value if need be, and the conversion is complete.
If xs:float
or
xs:double
, then xs:decimal
value, within the set of
xs:decimal
values that the implementation is
capable of representing, that is numerically closest to
xs:decimal
, (see
xs:float
or xs:double
values
NaN
, INF
, or -INF
, an
error is raised
If xs:boolean
, 1.0
if 1
or true
and to 0.0
if
0
or false
and the
conversion is complete.
If xdt:untypedAtomic
or xs:string
, see
When a value of any simple type is cast as xs:integer
, the
xs:integer
value
If xs:integer
, or a type derived
from xs:integer
, then xs:integer
value
if need be, and the conversion is complete.
If xs:decimal
, xs:float
or
xs:double
, then xs:integer
. Thus, casting 3.1456
returns 3
and -17.89
returns
-17
. Casting 3.124E1
returns 31
. If xs:float
or
xs:double
values NaN
,
INF
, or -INF
, an error is raised
If xs:boolean
, 1
if 1
or true
and to 0
if 0
or false
and the conversion is complete.
If xdt:untypedAtomic
or xs:string
, see
When a value of type xdt:untypedAtomic
, xs:string
,
a type derived from xs:string
,
xdt:yearMonthDuration
or xdt:dayTimeDuration
is
cast as xs:duration
, xdt:yearMonthDuration
or
xdt:dayTimeDuration
,
If
If xs:duration
, or a type derived
from xs:duration
, but not
xdt:dayTimeDuration
or a type derived from
xdt:dayTimeDuration
, and xdt:yearMonthDuration
, then
If xs:duration
, or a type derived
from duration
, but not
xdt:yearMonthDuration
or a type derived from
xdt:yearMonthDuration
, and xdt:dayTimeDuration
, then
If xdt:yearMonthDuration
or xdt:dayTimeDuration
, and xs:duration
, then
If xdt:yearMonthDuration
and xdt:dayTimeDuration
, the cast is permitted and returns a xdt:dayTimeDuration
with value 0.0 seconds.
If xdt:dayTimeDuration
and xdt:yearMonthDuration
, the cast is permitted and returns a xdt:yearMonthDuration
with value 0 months.
If xdt:untypedAtomic
or xs:string
, see
Note that casting from xs:duration
to
xdt:yearMonthDuration
or xdt:dayTimeDuration
loses
information. To avoid this, users can cast the xs:duration
value to both an xdt:yearMonthDuration
and an
xdt:dayTimeDuration
and work with both values.
In several situations, casting to date and time types requires the extraction
of a component from fn:current-dateTime
and converting it to an
xs:string
. These conversions must follow certain rules. For
example, converting an xs:integer
year value requires
converting to an xs:string
with four or more characters, preceded
by a minus sign if the value is negative.
This document defines four functions to perform these conversions. These functions are for illustrative purposes only and make no recommendations as to style or efficiency. References to these functions from the following text are not normative.
The arguments to these functions come from functions defined in this document. Thus, the functions below assume that they are correct and do no range checking on them.
Conversion from primitive types to date and time types follows the rules below.
When a value of any primitive type is cast as
xs:dateTime
, xs:time
,
xs:date
, xs:gYearMonth
,
xs:gYear
, xs:gMonthDay
,
xs:gDay
, or xs:gMonth
,
let eg:convertYearToString(
fn:year-from-dateTime( fn:current-dateTime() ))
,
let eg:convertTo2CharString(
fn:month-from-dateTime( fn:current-dateTime() ))
,
let eg:convertTo2CharString(
fn:day-from-dateTime( fn:current-dateTime() ))
.
When a value of any primitive type is cast as
xs:dateTime
, the xs:dateTime
value
If xs:dateTime
, then
If xs:date
, then let
eg:convertYearToString( fn:year-from-date(
))
, let eg:convertTo2CharString( fn:month-from-date(
))
, let eg:convertTo2CharString( fn:day-from-date(
))
and let eg:convertTZtoString( fn:timezone-from-date(
))
; xs:dateTime( fn:concat(
, '-',
, '-',
, 'T00:00:00 '
, ) )
.
If xdt:untypedAtomic
or
xs:string
, see
When a value of any primitive type is cast as xs:time
,
the xs:time
value
If xs:time
, then
If xs:dateTime
, then
xs:time( fn:concat(
eg:convertTo2CharString( fn:hours-from-dateTime(
)), ':', eg:convertTo2CharString( fn:minutes-from-dateTime(
)), ':', eg:convertSecondsToString( fn:seconds-from-dateTime(
)), eg:convertTZtoString( fn:timezone-from-dateTime(
)) ))
.
If xdt:untypedAtomic
or xs:string
, see
When a value of any primitive type is cast as xs:date
,
the xs:date
value
If xs:date
, then
If xs:dateTime
, then let
eg:convertYearToString( fn:year-from-dateTime(
))
, let eg:convertTo2CharString( fn:month-from-dateTime(
))
, let eg:convertTo2CharString( fn:day-from-dateTime(
))
and let eg:convertTZtoString(fn:timezone-from-dateTime(
))
; xs:date( fn:concat(
, '-',
, '-',
) )
.
If xdt:untypedAtomic
or xs:string
, see
When a value of any primitive type is cast as
xs:gYearMonth
, the xs:gYearMonth
value
If xs:gYearMonth
, then
If xs:dateTime
, then let
eg:convertYearToString( fn:year-from-dateTime(
))
, let eg:convertTo2CharString( fn:month-from-dateTime(
))
and let eg:convertTZtoString( fn:timezone-from-dateTime(
))
; xs:gYearMonth( fn:concat(
, '-',
) )
.
If xs:date
, then let
eg:convertYearToString( fn:year-from-date(
))
, let eg:convertTo2CharString( fn:month-from-date(
))
and let eg:convertTZtoString( fn:timezone-from-date(
))
; xs:gYearMonth( fn:concat(
, '-',
) )
.
If xdt:untypedAtomic
or xs:string
, see
When a value of any primitive type is cast as xs:gYear
,
the xs:gYear
value
If xs:gYear
, then
If xs:dateTime
, let
eg:convertYearToString( fn:year-from-dateTime(
))
and let eg:convertTZtoString( fn:timezone-from-dateTime(
))
; xs:gYear(fn:concat(
))
.
If xs:date
, let
eg:convertYearToString( fn:year-from-date(
))
; and let eg:convertTZtoString( fn:timezone-from-date(
))
; xs:gYear(fn:concat(
))
.
If xdt:untypedAtomic
or xs:string
, see
When a value of any primitive type is cast as
xs:gMonthDay
, the xs:gMonthDay
value
If xs:gMonthDay
, then
If xs:dateTime
, then let
eg:convertTo2CharString( fn:month-from-dateTime(
))
, let eg:convertTo2CharString( fn:day-from-dateTime(
))
and let eg:convertTZtoString( fn:timezone-from-dateTime(
))
; xs:gYearMonth( fn:concat(
'--',
'-',
) )
.
If xs:date
, then let
eg:convertTo2CharString( fn:month-from-date(
))
, let eg:convertTo2CharString( fn:day-from-date(
))
and let eg:convertTZtoString( fn:timezone-from-date(
))
; xs:gYearMonth( fn:concat(
'--',
, '-',
) )
.
If xdt:untypedAtomic
or xs:string
, see
When a value of any primitive type is cast as xs:gDay
,
the xs:gDay
value
If xs:gDay
, then
If xs:dateTime
, then let
eg:convertTo2CharString( fn:day-from-dateTime(
))
and let eg:convertTZtoString( fn:timezone-from-dateTime(
))
; xs:gDay(
fn:concat( '---'
, ))
.
If xs:date
, then let
eg:convertTo2CharString( fn:day-from-date(
))
and let eg:convertTZtoString( fn:timezone-from-date(
))
; xs:gDay(
fn:concat( '---'
, ))
.
If xdt:untypedAtomic
or xs:string
, see
When a value of any primitive type is cast as xs:gMonth
,
the xs:gMonth
value
If xs:gMonth
, then
If xs:dateTime
, then let
eg:convertTo2CharString( fn:month-from-dateTime(
))
and let eg:convertTZtoString( fn:timezone-from-dateTime(
))
; xs:gMonth(
fn:concat( '--'
, ))
.
If xs:date
, then let
eg:convertTo2CharString( fn:month-from-date(
))
and let eg:convertTZtoString( fn:timezone-from-date(
))
; xs:gMonth(
fn:concat( '--'
, ))
.
If xdt:untypedAtomic
or xs:string
, see
When a value of any primitive type is cast as xs:boolean
, the
xs:boolean
value
If xs:boolean
, then
If xs:float
, xs:double
,
xs:decimal
or xs:integer
and
0
, +0
, -0
,
0.0
, 0.0E0
or NaN
, then
false
.
If xs:float
, xs:double
,
xs:decimal
or xs:integer
and
true
.
If xdt:untypedAtomic
or xs:string
, see
Values of type xs:base64Binary
can be cast as
xs:hexBinary
and vice versa, since the two types have the same
value space. Casting to xs:base64Binary
and
xs:hexBinary
is also supported from the same type and from
xdt:untypedAtomic
, xs:string
and subtypes of
xs:string
using
Casting to xs:anyURI
is supported only from the same type,
xdt:untypedAtomic
or xs:string
.
When a value of any primitive type is cast as xs:anyURI
, the
xs:anyURI
value
If xdt:untypedAtomic
or xs:string
see
Casting a value to a derived type can be separated into four cases. Note that
xdt:untypedAtomic
, xs:integer
and the two derived
types of xs:duration
:xdt:yearMonthDuration
and xdt:dayTimeDuration
are treated as primitive types.
When
When
When the derived type is derived, directly or indirectly, from a
different primitive type than the primitive type of
When
It is always possible to cast a value of any atomic type to an atomic type from
which it is derived, directly or indirectly, by restriction. For example, it is
possible to cast an xs:unsignedShort
to an
xs:unsignedInt
, an xs:integer
, or an
xs:decimal
. Since the value space of the original type is a subset
of the value space of the target type, such a cast is always successful. The
result will have the same value as the original, but will have a new type annotation.
It is possible to cast an xs:byte
can be cast as
xs:unsignedShort
, provided the value is not negative.
If the value does not conform to the facets defined for the target type, then an
error is raised xs:string
, in the case of types that have no canonical
lexical representation defined for them).
Note that this will cause casts to fail if the pattern excludes the canonical
lexical representation of the source type. For example, if the type
my:distance
is defined as a restriction of xs:decimal
with a pattern that requires two digits after the decimal point, casting of an
xs:integer
to my:distance
will always fail, because
the canonical representation of an xs:integer
does not conform to
this pattern.
In some cases, casting from a parent type to a derived type requires special
rules. See xdt:yearMonthDuration
and xdt:dayTimeDuration
. See xs:ENTITY
and types derived from it.
The
value space of ENTITY is the set of all strings that match the
NCName production ... and have been
declared as an unparsed entity in a document type definition.
However,
xs:ENTITY
match declared unparsed entities. Thus, this rule is relaxed in this specification and, in casting to xs:ENTITY
and types derived from it, no check is made that the values correspond to declared unparsed entities.
When the
Cast the
If xs:string
or xdt:untypedAtomic
, check its value against the pattern facet of
Cast the value to the primitive type of
Cast the value down to the
Some of the more significant changes that appear in this version of the document are listed below. A complete list of comments against the previous version of the document can be found in the
Comments 1794 and 1824 are still open and will be discussed after publication of this draft. The I18N WG has requested that a 'health warning' be added to help users aviod pitfalls in working with dates and times with and without timezones. The WGs agreed to this request in principle but the exact wording and the form it will take is still under discussion.
A new function fn:escape-html-uri
has been added to mimic the html 4.0 URI escaping behavior on attributes. The serialization specification escapes URIs in this manner and it was felt to be useful to make this functionality available as a function.
Casting from xs:string
and xdt:untypedAtomic
to derived types has been clarified. If the derived type is restricted by a pattern, the lexical form is first checked against the pattern. See
Section xs:NOTATION
to
xs:NOTATION
, since it is an abstract type, casting is permitted from one subtype of xs:NOTATION
to another. The entry in the table at the intersection of xs:NOTATION
and xs:NOTATION
has consequently been changed to "M".
This document no longer supports leap seconds. Wording has been changed in several places to reflect this decision.
We have been made aware of ongoing work to provide URI-based names for collations and
collation algorithms and to create an IANA registry for such names. See member-only
communication:
The error text provided with these errors is non-normative.
Unidentified error.
This error is raised whenever an attempt is made to divide by zero.
This error is raised whenever numeric operations result in an overflow or underflow.
.
This appendix summarizes the relationship between certain functions defined in
The evaluation of the arguments to the functions defined in this document depends on
whether the XPath 1.0 compatibility mode is on or off. See
If the expected type is a single item or an optional single item, (examples:
xs:string, xs:string?, xdt:untypedAtomic, xdt:untypedAtomic?,
node(), node()?, item(), item()?
), then the given value
V
is effectively replaced by fn:subsequence(V, 1, 1)
.
If the expected type is xs:string
or xs:string?
,
then the given value V
is effectively replaced by fn:string(V)
.
If the expected type is numeric or optional numeric, then the given value
V
is effectively replaced by fn:number(V)
.
Otherwise, the given value is unchanged.
XQuery 1.0 and XPath 2.0 | XPath 1.0 | Notes |
---|---|---|
|
last() => number
|
Precision of numeric results may be different. |
|
position() => number
|
Precision of numeric results may be different. |
|
count(node-set) => number
|
Precision of numeric results may be different. |
|
id(object) => node-set
|
XPath 2.0 behavior is different for boolean and numeric arguments. The recognition of a node as an id value is sensitive to the manner in which the datamodel is constructed. In XPath 1.0 the whole string is treated as a unit. In XPath 2.0 each string is treated as a list. |
|
local-name(node-set?) => string
|
If compatibility mode is off, an error will occur if argument has more than one node. |
|
||
|
namespace-uri(node-set?) => string
|
If compatibility mode is off, an error will occur if argument has more than one node. |
|
||
|
name(node-set?) => string
|
If compatibility mode is off, an error will occur if argument has more
than one node. The rules for determining the prefix are more precisely
defined in |
|
string(object) => string
|
If compatibility mode is off, an error will occur if argument has more than one node. Representations of numeric values are XPath 1.0 compatible except for the special values positive and negative infinity, and for values outside the range 1.0e-6 to 1.0e+6. |
|
||
|
concat(string, string, string*) => string
|
If compatibility mode is off, an error will occur if argument has more than one node or if argument is a number or a boolean. If compatibility mode on, implicit conversion is performed. |
|
starts-with(string, string) => boolean
|
In 1.0, returns false if the first argument is
an empty node-set. In 2.0, returns () . If compatibility
mode is off, an error will occur if argument has more than one node or
if argument is a number or a boolean. If compatibility mode is on,
implicit conversion is performed. |
|
||
|
contains(string, string) => boolean
|
In 1.0, returns false if the first argument is
an empty node-set. In 2.0, returns () . If compatibility
mode is off, an error will occur with more than one node and a
non-string argument results in a type error. |
|
||
|
substring-before(string, string) => string
|
In 1.0, returns "" if the first argument is an
empty node-set. In 2.0, returns () . If compatibility mode
is off, numbers and booleans will give errors. Multiple nodes and more
than one value will also give error. |
|
||
|
substring-after(string, string) => string
|
In 1.0, returns "" if the first argument is an
empty node-set. In 2.0, returns () . If compatibility mode
is off, numbers and booleans will give errors. Multiple nodes and more
than one value will also give error. |
|
||
|
substring(string, number, number?) => string
|
In 1.0, returns "" if the first argument is an
empty node-set. In 2.0, returns () . |
|
||
|
string-length(string?) => number
|
If you apply fn:string-length(@a) == 0 ; In 1.0
returns true if @a does not exist. In 2.0 returns false. |
|
||
|
normalize-space(string?) => string
|
In 1.0, returns "" if the first argument is an
empty node-set. In 2.0, returns () . If compatibility mode
is off, numbers and booleans will give errors for first arg. Also,
multiple nodes will give error. |
|
||
|
translate(string, string, string)=> string
|
. |
|
boolean(object) => boolean
|
|
|
not(boolean) => boolean
|
|
|
true() => boolean
|
|
|
false() => boolean
|
|
|
lang(string) => boolean
|
If compatibility mode is off, numbers and booleans will give errors. Also, multiple nodes will give error. If compatibility mode is on, implicit conversion is performed. |
|
number(object?) => number
|
Error if argument has more than one node when not in compatibility node. |
|
||
|
sum(node-set) => number
|
2.0 raises an error if sequence contains values that cannot be added
together such as NMTOKENS and other subtypes of string. 1.0 returns NaN .
|
|
floor(number)=> number
|
In 2.0, if argument is () , the result is () .
In 1.0, the result is NaN . If compatibility mode is off, an
error will occur with more than one node. If compatibility mode is on,
implicit conversion is performed. |
|
ceiling(number)=> number
|
In 2.0, if argument is () , the result is () .
In 1.0, the result is NaN . If compatibility mode is off, an
error will occur with more than one node. If compatibility mode is on,
implicit conversion is performed. |
|
round(number)=> number
|
In 2.0, if argument is () , the result is () .
In 1.0, the result is NaN . If compatibility mode is off, an
error will occur with more than one node. If compatibility mode is on,
implicit conversion is performed. |
Certain functions that were proposed for inclusion in this function library have been excluded on the basis that it is straightforward for users to implement these functions themselves using XSLT 2.0 or XQuery 1.0.
This Appendix provides sample implementations of some of these functions.
To emphasize that these functions are examples of functions that vendors may write, their names carry the prefix 'eg'. Vendors are free to define such functions in any namespace. A group of vendors may also choose to create a collection of such useful functions and put them in a common namespace.
In some situations, users may want to provide default values for missing
information that may be signaled by elements that are omitted, have no value or
have the empty sequence as their value. For example, a missing middle initial
may be indicated by omitting the element or a non-existent bonus signaled with
an empty sequence. This section includes examples of functions that provide such
defaults. These functions return xdt:anyAtomicType*
. Users may want
to write functions that return more specific types.
If the first argument is the empty sequence or an element without simple or complex content, if-empty() returns the second argument; otherwise, it returns the content of the first argument.
XSLT implementation
XQuery implementation
If the first argument is the empty sequence, if-absent() returns the second argument; otherwise, it returns the content of the first argument.
XSLT implementation
XQuery implementation
This function returns a sequence containing all the distinct items in $arg1 and $arg2, in an undefined order.
XSLT implementation
XQuery implementation
This function returns a sequence containing all the distinct items that appear in both $arg1 and $arg2, in an undefined order.
XSLT implementation>
XQuery implementation
This function returns a sequence containing all the distinct items that appear in $arg1 but not in $arg2, in an undefined order.
XSLT implementation
XQuery implementation
This function returns a sequence of positive integers giving the positions within
the sequence $seqParam
of nodes that are identical to $srchParam
.
The nodes in the sequence $seqParam
are compared with
$srchParam
under the rules for the is
operator. If a
node compares identical, then the position of that node in the sequence
$srchParam
is included in the result.
If the value of $seqParam
is the empty sequence, or if no node in
$seqParam
matches $srchParam, then the empty sequence is returned.
The index is 1-based, not 0-based.
The result sequence is in ascending numeric order.
XSLT implementation
XQuery implementation
Returns a xs:string
consisting of a given number of copies of an
xs:string
argument concatenated together.
XSLT implementation
XQuery implementation
This returns the zero-length string if $padString
is the empty
sequence, which is consistent with the general principle that if an
xs:string
argument is the empty sequence it is treated as if it
were the zero-length string.
This function illustrates one possible implementation of a distinct-nodes function. It removes duplicate nodes by identity, preserving the first occurrence of each node.
XPath
XSLT implementation
XQuery implementation
The following schema defines the types in the
xdt:
namespace identified by the namespace name
http://www.w3.org/2005/xpath-datatypes
.
You can retrieve the normative schema for this namespace from
This appendix provides a summary of features defined in this specification whose effect is explicitly
The destination of the trace output is
For xs:integer
operations, implementations that support limited-precision integer operations
For xs:decimal
values the number of digits of precision returned by the numeric operators is
It is
For
The ability to decompose strings into collation units suitable for substring matching is an
All
Various aspects of the processing provided by