Copyright	(c) Chris Kuklewicz 2006, (c) shelarcy 2012, derived from (c) The University of Glasgow 2001
License	BSD-style (see the file LICENSE)
Maintainer	libraries@haskell.org
Stability	experimental
Portability	non-portable (regex-base needs MPTC+FD)
Safe Haskell	None
Language	Haskell98

Text.Regex

Contents

Regular expressions

Description

Regular expression matching. Uses the POSIX regular expression interface in Text.Regex.TDFA.

Synopsis

Regular expressions

data Regex :: *

The TDFA backend specific Regex type, used by this module's RegexOptions and RegexMaker

Instances

RegexOptions Regex CompOption ExecOption

mkRegex :: String -> Regex

Makes a regular expression with the default options (multi-line, case-sensitive). The syntax of regular expressions is otherwise that of egrep (i.e. POSIX "extended" regular expressions).

mkRegexWithOpts

Arguments

:: String	The regular expression to compile
-> Bool	`True` `<=>` `'^'` and `'$'` match the beginning and end of individual lines respectively, and `'.'` does not match the newline character.
-> Bool	`True` `<=>` matching is case-sensitive
-> Regex	Returns: the compiled regular expression

Makes a regular expression, where the multi-line and case-sensitive options can be changed from the default settings.

matchRegex

Arguments

:: Regex	The regular expression
-> String	The string to match against
-> Maybe [String]	Returns: `Just strs` if the match succeeded (and `strs` is the list of subexpression matches), or `Nothing` otherwise.

Match a regular expression against a string

matchRegexAll

Arguments

:: Regex

The regular expression

-> String

The string to match against

-> Maybe (String, String, String, [String])

Returns: Nothing if the match failed, or:

 Just ( everything before match,
        portion matched,
        everything after the match,
        subexpression matches )

Match a regular expression against a string, returning more information about the match.

subRegex

Arguments

:: Regex	Search pattern
-> String	Input string
-> String	Replacement text
-> String	Output string

Replaces every occurance of the given regexp with the replacement string.

In the replacement string, "\1" refers to the first substring; "\2" to the second, etc; and "\0" to the entire match. "\\\\" will insert a literal backslash.

This does not advance if the regex matches an empty string. This misfeature is here to match the behavior of the the original Text.Regex API.

splitRegex :: Regex -> String -> [String]

Splits a string based on a regular expression. The regular expression should identify one delimiter.

This does not advance and produces an infinite list of [] if the regex matches an empty string. This misfeature is here to match the behavior of the the original Text.Regex API.