fn:matches

Returns true if the given string matches the given regular expression.

matches($input as xs:string?, $pattern as xs:string) ➔ xs:boolean

Arguments
	$input	xs:string?	The string to be matched against a regular expression
	$pattern	xs:string	The regular expression
Result		xs:boolean

matches($input as xs:string?, $pattern as xs:string, $flags as xs:string) ➔ xs:boolean

Arguments
	$input	xs:string?	The string to be matched against a regular expression
	$pattern	xs:string	The regular expression
	$flags	xs:string	Flags that control the interpretation of the regular expression
Result		xs:boolean

Namespace

http://www.w3.org/2005/xpath-functions

Links to W3C specifications

XPath 3.1 Functions and Operators

Notes on the Saxon implementation

Saxon 9.3 introduced support for the q flag, and for XPath 3.0 regular expression enhancements, provided XPath 3.0 is enabled.

Saxon implements some extensions to the flags argument. The value of this argument contains the standard flags defined in the spec (i, m, s, x, q) followed optionally by a semicolon and then Saxon-specific flags. The Saxon-specific flags are:

j - Use the standard Java regular expression engine, allowing native Java regex syntax. This is supported on both the Java platform and the .NET platform. This allows, for example, the use of "\b" in a regular expression to match word boundaries.

Note: On the Java platform, this can also be achieved using the flag "!"; this was never formally supported and is likely to be withdrawn in a future Saxon version.
n - Use the standard .NET regular expression engine, allowing native .NET regex syntax. This is supported on the .NET platform only.
g - Switch on diagnostics. Not currently used.
k - Treat unknown Unicode block names as matching any character (this is the default for XSD 1.1). This option applies to the Saxon regular expression engine only.
K - Treat unknown Unicode block names as an error (this is the default for XSD 1.0 and for XPath/XSLT/XQuery). This option applies to the Saxon regular expression engine only.

For Saxon 10 and earlier releases, if the platform-native regex engine is used (Java or .NET) then the syntax for the replacement expression in the third argument of fn:replace() still follows the XPath rules, not the platform native rules. This means, for example, that the syntax ${name} cannot be used in a reference to a named captured group. This will change in Saxon 11 so the replacement string follows the platform native rules. (On .NET this means that a literal '$' sign is escaped as '\$' in Saxon 10, but as '$$' in Saxon 11).