Text.Regex

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

Regular expressions

data Regex

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

Instances

RegexLike Regex String

RegexLike Regex ByteString

RegexLike Regex ByteString

RegexOptions Regex CompOption ExecOption

RegexContext Regex String String

RegexContext Regex ByteString ByteString

RegexContext Regex ByteString ByteString

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.