This is the XML schema for the Rule Language as defined by
the RIF-Core dialect.
The schema is based on the following EBNF for the RIF-Core Rule Language
(prepared for generalization to the RIF-BLD and RIF-PRD Rule Languages):
Document ::= IRIMETA? 'Document' '(' Base? Prefix* Import* Group? ')'
Base ::= 'Base' '(' ANGLEBRACKIRI ')'
Prefix ::= 'Prefix' '(' NCName ANGLEBRACKIRI ')'
Import ::= IRIMETA? 'Import' '(' LOCATOR PROFILE? ')'
Group ::= IRIMETA? 'Group' '(' (RULE | Group)* ')'
RULE ::= (IRIMETA? 'Forall' Var+ '(' CLAUSE ')') | CLAUSE
CLAUSE ::= Implies | ATOMIC
Implies ::= IRIMETA? (ATOMIC | 'And' '(' ATOMIC* ')') ':-' FORMULA
LOCATOR ::= ANGLEBRACKIRI
PROFILE ::= ANGLEBRACKIRI
Note that this is an extension of the syntax for the RIF-Core Condition Language (CoreCond.xsd).