Basic characteristics of regular expressions
Following are notable characteristics of regular expressions as defined on the NetScaler appliance:
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A regular expression always begins with the string “re” followed by a pair of delimiting characters (called delimiters) that enclose the regular expression that you want to use.
For example, re#\<regex_pattern\># uses the number sign (#) as a delimiter.
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A regular expression cannot exceed 1499 characters.
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Digit matching can be done by using the string \d (a backslash followed by d).
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White space can be represented by using \s (a backslash followed by s).
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A regular expression can contain white spaces.
Following are the differences between the NetScaler syntax and the PCRE syntax:
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The NetScaler does not allow back references in regular expressions.
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You should not use recursive regular expressions.
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The dot meta-character also matches the newline character.
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Unicode is not supported.
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The operation SET_TEXT_MODE(IGNORECASE) overrides the (?i) internal option in the regular expression.