Portability	non-portable (regex-base needs MPTC+FD)
Stability	experimental
Maintainer	libraries@haskell.org

Text.Regex

Contents

Regular expressions

Description

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

Synopsis

Regular expressions

data Regex

Instances

RegexLike Regex String
RegexLike Regex ByteString
RegexLike Regex ByteString
RegexContext Regex String String
RegexContext Regex ByteString ByteString
RegexContext Regex ByteString ByteString
RegexOptions Regex CompOption ExecOption
RegexMaker Regex CompOption ExecOption String
RegexMaker Regex CompOption ExecOption ByteString
RegexMaker Regex CompOption ExecOption ByteString
RegexMaker Regex CompOption ExecOption (Seq Char)
RegexLike Regex (Seq Char)
RegexContext Regex (Seq Char) (Seq Char)

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.