Text.Regex.PCRE.Light.Extra

pcre-light utility functions for more user friendly usage. Instead of adding execution and compile options to the matching and compiling functions, the options are added to the regular expression to be compiled or run. Furthermore support for different matching return types (using typeclass MatchResult) and different regular expression types (compiled or uncompiled using typeclass RegexLike) are supported.

examples using GHC's -XOverloadedStrings flag:

simple matching with uncompiled pattern abc of type ByteString:

>>> ("abc" =~ ("abc" :: ByteString)) :: Bool
True

case insensitive matching with uncompiled pattern of type ByteString:

>>> ("AbCasf" =~ caseSensitive False "abc") :: Bool
True

>>> ("AbCasf" =~ caseSensitive False "abc") :: Maybe [ByteString]
Just ["AbC"]

Documentation

data RegexPattern

Uncompiled regular expression with compile and execution options. Compiles to RegexExecPattern preserving execution options.

Constructors

Regex [PCREOption] [PCREExecOption] ByteString

Instances

RegexLike RegexPattern

data RegexExecPattern

Compiled regular expression with execution results.

Constructors

RegexExec [PCREExecOption] Regex

Instances

RegexLike RegexExecPattern

class MatchResult x where

Typeclass defining automatic conversion of PCRE matching results to user defined type. Used in typeclass RegexLike and function (=~).

Methods

convert :: Maybe [ByteString] -> x

Instances

MatchResult Bool

MatchResult (Maybe [ByteString])

class RegexLike rl where

RegexLike types can be compiled to regular epxression or directly used as regular expression.

Associated Types

type RegexType rl

Type of compiled regular expression for instance rl.

Methods

compile :: rl -> Either String (RegexType rl)

compiles a perl-compatible regular expression to an executable regular expression. See Text.Regex.PCRE.Light.compileM.

match :: MatchResult res => rl -> ByteString -> res

matches a Bytestring with a regular expression of type rl. If rl needs to be compiled (for example when rl ~ ByteString or rl ~ RegexPattern) but is invalid, an exception will be thrown. It is recommended to use compiled patterns with match for better error handling.

Instances

RegexLike ByteString

RegexLike Regex

RegexLike RegexExecPattern

RegexLike RegexPattern

(=~) :: (RegexLike regex, MatchResult ret) => ByteString -> regex -> ret

matches a ByteString with a regular expression.

cfg :: [PCREOption] -> [PCREExecOption] -> ByteString -> RegexPattern

create regular expression with compile and execution options.

withExecOpts :: [PCREExecOption] -> Regex -> RegexExecPattern

Add execution options to compiled regular expression of pcre-light's compiled regular expression type Regex

caseSensitive :: Bool -> ByteString -> RegexPattern

Create case sensitive (first parameter is True) or case insensitive regular expression from pattern.