See also: IRC log
<inserted> Harold's slides: https://lists.w3.org/Archives/Public/www-archive/2016Jun/att-0003/FHIR_RDF_Extensions_v2.pdf
harold: Pattern, minValue and maxValue are now implemented.
<hsolbrig> file:///Users/mrf7578/Development/fhir/build/publish/patient.shex.html
harold: Also put comments in the shex.
<hsolbrig> http://hl7-fhir.github.io/medication.shex.html
harold: Eric wondered if we could drop the turtle template language. Eric changed commas to semicolons.
<hsolbrig> http://hl7-fhir.github.io/fhir.shex
harold: Also created fhir.shex,
which has all the shex definitions of everything.
... I want to remove the comments, because they make it much
bigger.
... When we do something like Patient.shex, all of these shex
definitions are CLOSED.
... When we're pulling definitions into a bundle it's wide open
-- it must have at least one type arc.
... In the fhir.shex it makes more sense to change that wide
open def to one that explicitly lists all of the possible
resources.
... But that would only be in the fhir.shex.
dbooth: CLOSED means a closed content model?
harold: Yes. If you have something else it's an error.
dbooth: What does "<Resource> {a .+;" mean?
harold: the dot is a wildcard, meaning anything.
eric: regarding CLOSED, on one
hand is the RDF ideal of allowing other content and ignore it
you don't care about it.
... Another is, for clinical exchange, where you know the
content model and you don't want anything else. Even the
extensions fit into the closed content model, which means that
the typos get caught.
harold: whenever I generate a new version of shex I test all of the FHIR examples, and this works against them.
dbooth: The passing examples?
harold: yes. No failing examples yet.
james: Suggest enumerating as
little as possible.
... To reduce maintenance difficulties.
... Having an abstract class may be better.
harold: grahame wanted a case with completely closed system.
james: Then you could never subclass it.
harold: To extend a core
resource, you extend it with tagged value pairs.
... I'm not allowed to add a Price element to the Medication
element.
... But I can create an extension by adding an extension
element.
eric: it is a closed content model, you cannot add to it, but one thing that is in there is an extension mechanism with the FHIR keyword and grammar.
dbooth: So if you want to
subclass in the RDF world, you can do that until you want to
send your content as FHIR RDF to someone else. Then you have to
limit what you send to ONLY the FHIR RDF portion.
... We could consider standardizing a way to put arbitrary RDF
in the FHIR extension mechanism.
harold: I need two different
kinds of code, to handing FHIR RDF extensions: one for basic
FHIR RDF, the other for the extensions.
... Our ideal approach would be to have the extensions and core
FHIR resources be similar, though with an extension we're not
guaranteed to have the schema available.
ISSUE: Should we try to unify the treatment of extensions with regular resources?
<trackbot> Created ISSUE-37 - Should we try to unify the treatment of extensions with regular resources?. Please complete additional details at <http://www.w3.org/2014/HCLS/track/issues/37/edit>.
shahram: This works if extensions are not modifying extensions.
harold: Correct. Extensions can
theoretically override the base semantics.
... I vaguely remember hearing someone say that you can change
the types is the core elements.
... But I'm trying to address Well Behaved extensions.
eric: At least in the past there
were modifier and non-modifier extensions. Non-modifier
extensions could be safely ignored; modifier extensions could
not.
... That meant that you have to check for modifier extensions
before you process.
... They need to be hidden from someone who will interpret it
monotonically.
harold: This discussion is for
Well Behaved non-nodifier (monotonic) extensions
... One option is the ideal translation. An alternative is to
use the FHIR extension wrapper on the outside, but also use the
preferred representation inside.
... This requires two kinds of typing, but gives consistent
typing.
... Another alternative 2, is to have a first-class predicate
as the tag.
... My hope is that we can come out with the ideal, for
non-monotonic extensions.
... But this leads to an interesting condition when discussing
open/closed validation.
... If this form is used, then none of the shex forms can be
closed.
... But a validator could close it to the extent of only
allowing unrecognized predicates whose object is of type
fhir:Extension.
... We'd have to do some work to make this work in shex.
... Also, for every fhir type, we need to allow an optional
type arc.
... That seems reasonable.
... We could declare the range of
fhir;Extension.valueIdentifier to be Identifier, but we're not
doing that now.
... Should we stick with literal RDF translation? It requires
less explaining. Disadvantage is that it is much harder in
SPARQL to use.
... Migrating from extension to core is non-trivial this
way.
... Doing it the suggested way allows a more uniform way to
treat extensions and core resources.
michael: Trying to figure out how this affects the generation of instances
harold: This is an instance from a FHIR example.
<hsolbrig> diagnosticreport-examples-general.ttl
harold: slides 10-13 discuss
modifiers
... The fhir:Quantity.comparator [ fhir:value ",>" ];
non-monotonically changes the meaning of the value.
ISSUE: How to handle modifiers?
<trackbot> Created ISSUE-38 - How to handle modifiers?. Please complete additional details at <http://www.w3.org/2014/HCLS/track/issues/38/edit>.
Harold: One possibility would be to post these questions on zulip
dbooth: Hoping to schedule a discussion of FHIR vocabulary and schema.org next week, 5pm ET.
ADJOURNED
This is scribe.perl Revision: 1.144 of Date: 2015/11/17 08:39:34 Check for newer version at http://dev.w3.org/cvsweb/~checkout~/2002/scribe/ Guessing input format: RRSAgent_Text_Format (score 1.00) Succeeded: i/harold: Pattern, minValue/Harold's slides: Succeeded: s|Harold's slides:|Harold's slides: https://lists.w3.org/Archives/Public/www-archive/2016Jun/att-0003/FHIR_RDF_Extensions_v2.pdf| No ScribeNick specified. Guessing ScribeNick: dbooth Inferring Scribes: dbooth Present: David_Booth EricP Harold_Solbrig Amol Brian_Pech Chad_Albert Craig_Parker James_Anderson Michael_Van_Der_Zel Shahram Found Date: 21 Jun 2016 Guessing minutes URL: http://www.w3.org/2016/06/21-hcls-minutes.html People with action items:[End of scribe.perl diagnostic output]