Default Query Language Binding
A Schematron schema with no language binding or a language attribute with the value xslt, in any mix of upper and lower case letters, shall use the following binding:
The query language used is the extended version of XPath specified in XSLT. Consequently, the data model used is the data model of those specifications.
The rule context is interpreted according to the Production 1 of XSLT. The rule context may be elements, attributes, comments and processing instructions.
The assertion test is interpreted according to Production 14 of XPath, as returning a boolean value.
The name query is interpreted according to Production 14 of XPath, as returning a string value. Typically, the select attribute contains an expression returning an element node: the name query takes the local or prefixed name of the node, not its value.
The value-of query is interpreted according to Production 14 of XPath, as returning a string value.
The let value is interpreted according to Production 14 of XPath, as returning a string value.
The notation for signifying the use of parameter of an abstract pattern is to prefix the name token with the $ character. This is a character not found as a delimiter in URLs or XPaths. The $ character not followed by the name of an in-scope parameter shall not be treated as a parameter name delimiter. Such a character may subsequently be used as a delimiter for a variable name or as a literal character.
A Schematron let expression is treated as an XSLT variable. The XSLT $ delimiter signifies the use of a variables in an context expression, assertion test, name query, value-of query or let expression. The $ character not followed by the name of an in-scope variable shall be treated as a literal character.
The XSLT key element may be used, in the XSLT namespace, before the pattern elements.
The attributes id, name and prefix should follow the rules for non-colonized names for the version of XML used by the document.