XSLT, 2nd Edition

Name

[2.0] matches()

Determines whether a given string matches a given regular expression.

Syntax

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

Inputs

An input string and a regular expression. The matches() function also supports an optional string defining flags that modify how the regular expression is processed.

Outputs

true if the string matches the regular expression; false otherwise.

Regular expressions are extremely powerful, so there are a number of details about how they work:

• If $input is the empty sequence, it is interpreted as a zero-length string. The matches() function can still return true in this situation. For example, matches((), '.?') is true, as is matches('', '.?').

• Regular expression matching does not use collations; the characters’ Unicode code points are compared. Cases in which different characters are considered equal in the world’s languages are not taken into account.

• Unless you use the ^ (start of line) or $ (end of line) characters as anchors in your regular expression, a string is considered a match if any part of it matches the regular expression.

• Unlike regular expressions used in the <xsl:analyze-string> element, curly braces ({ and }) are not doubled. (Curly braces used inside the regex attribute of <xsl:analyze-string> must be doubled so they aren’t interpreted as attribute value templates.)

• The $flags parameter modifies how the regular expression is processed. ...