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

Text.Regex.Posix.Wrap

Contents

High-level API
Low-level API
Miscellaneous
Compilation options
Execution options
Return codes

Description

WrapPosix.hsc exports a wrapped version of the ffi imports. To increase type safety, the flags are newtype'd. The other important export is a Regex type that is specific to the Posix library backend. The flags are documented in Text.Regex.Posix. The defaultCompOpt is (compExtended .|. compNewline).

The Regex, CompOption, and ExecOption types and their RegexOptions instance is declared. The =~ and =~~ convenience functions are defined.

The exported symbols are the same whether 1 is defined, but when it is not defined then getVersion == Nothing and all other exported values will call error or fail.

This module will fail or error only if allocation fails or a nullPtr is passed in.

2009-January : wrapMatchAll and wrapCount now adjust the execution option execNotBOL after the first result to take into account '\n' in the text immediately before the next matches. (version 0.93.3)

2009-January : wrapMatchAll and wrapCount have been changed to return all non-overlapping matches, including empty matches even if they coincide with the end of the previous non-empty match. The change is that the first non-empty match no longer terminates the search. One can filter the results to obtain the old behavior or to obtain the behavior of sed, where sed eliminates the empty matches which coincide with the end of non-empty matches. (version 0.94.0)

Synopsis

High-level API

data Regex Source

A compiled regular expression.

type RegOffset = Int64 Source

RegOffset is typedef int regoff_t on Linux and ultimately typedef long long __int64_t on Max OS X. So rather than saying 2,147,483,647 is all the length you need, I'll take the larger: 9,223,372,036,854,775,807 should be enough bytes for anyone, no need for Integer. The alternative is to compile to different sizes in a platform dependent manner with type RegOffset = (, which I do not want to do.

There is also a special value unusedRegOffset :: RegOffset which is (-1) and as a starting index means that the subgroup capture was unused. Otherwise the RegOffset indicates a character boundary that is before the character at that index offset, with the first character at index offset 0. So starting at 1 and ending at 2 means to take only the second character.

type RegOffsetT = Int32 Source

(=~) :: (RegexMaker Regex CompOption ExecOption source, RegexContext Regex source1 target) => source1 -> source -> targetSource

(=~~) :: (RegexMaker Regex CompOption ExecOption source, RegexContext Regex source1 target, Monad m) => source1 -> source -> m targetSource

Low-level API

type WrapError = (ReturnCode, String)Source

The return code will be retOk when it is the Haskell wrapper and not the underlying library generating the error message.

wrapCompile Source

Arguments

:: CompOption	Flags (bitmapped)
-> ExecOption	Flags (bitmapped)
-> CString	The regular expression to compile (ASCII only, no null bytes)
-> IO (Either WrapError Regex)	Returns: the compiled regular expression

wrapTest :: Regex -> CString -> IO (Either WrapError Bool)Source

wrapMatch :: Regex -> CString -> IO (Either WrapError (Maybe [(RegOffset, RegOffset)]))Source

wrapMatch returns offsets for the begin and end of each capture. Unused captures have offsets of unusedRegOffset which is (-1)

wrapMatchAll :: Regex -> CString -> IO (Either WrapError [MatchArray])Source

wrapMatchAll returns the offset and length of each capture. Unused captures have an offset of unusedRegOffset which is (-1) and length of 0.

wrapCount :: Regex -> CString -> IO (Either WrapError Int)Source

Miscellaneous

unusedRegOffset :: RegOffset Source

Compilation options

newtype CompOption Source

A bitmapped CInt containing options for compilation of regular expressions. Option values (and their man 3 regcomp names) are

compBlank which is a completely zero value for all the flags. This is also the blankCompOpt value.
compExtended (REG_EXTENDED) which can be set to use extended instead of basic regular expressions. This is set in the defaultCompOpt value.
compNewline (REG_NEWLINE) turns on newline sensitivity: The dot (.) and inverted set [^ ] never match newline, and ^ and $ anchors do match after and before newlines. This is set in the defaultCompOpt value.
compIgnoreCase (REG_ICASE) which can be set to match ignoring upper and lower distinctions.
compNoSub (REG_NOSUB) which turns off all information from matching except whether a match exists.

Constructors

CompOption CInt

compBlank :: CompOption Source

A completely zero value for all the flags. This is also the blankCompOpt value.

compExtended :: CompOption Source

compIgnoreCase :: CompOption Source

compNoSub :: CompOption Source

compNewline :: CompOption Source

Execution options

newtype ExecOption Source

A bitmapped CInt containing options for execution of compiled regular expressions. Option values (and their man 3 regexec names) are

execBlank which is a complete zero value for all the flags. This is the blankExecOpt value.
execNotBOL (REG_NOTBOL) can be set to prevent ^ from matching at the start of the input.
execNotEOL (REG_NOTEOL) can be set to prevent $ from matching at the end of the input (before the terminating NUL).

Constructors

ExecOption CInt

execBlank :: ExecOption Source

A completely zero value for all the flags. This is also the blankExecOpt value.

execNotBOL :: ExecOption Source

execNotEOL :: ExecOption Source

Return codes

newtype ReturnCode Source

ReturnCode is an enumerated CInt, corresponding to the error codes from man 3 regex:

retBadbr (REG_BADBR) invalid repetition count(s) in { }
retBadpat (REG_BADPAT) invalid regular expression
retBadrpt (REG_BADRPT) ?, *, or + operand invalid
retEcollate (REG_ECOLLATE) invalid collating element
retEctype (REG_ECTYPE) invalid character class
retEescape (REG_EESCAPE) \ applied to unescapable character
retEsubreg (REG_ESUBREG) invalid backreference number
retEbrack (REG_EBRACK) brackets [ ] not balanced
retEparen (REG_EPAREN) parentheses ( ) not balanced
retEbrace (REG_EBRACE) braces { } not balanced
retErange (REG_ERANGE) invalid character range in [ ]
retEspace (REG_ESPACE) ran out of memory
retNoMatch (REG_NOMATCH) The regexec() function failed to match

Constructors

ReturnCode CInt

Instances

Eq ReturnCode
Show ReturnCode

retBadbr :: ReturnCode Source

retBadpat :: ReturnCode Source

retBadrpt :: ReturnCode Source

retEcollate :: ReturnCode Source

retEctype :: ReturnCode Source

retEescape :: ReturnCode Source

retEsubreg :: ReturnCode Source

retEbrack :: ReturnCode Source

retEparen :: ReturnCode Source

retEbrace :: ReturnCode Source

retErange :: ReturnCode Source

retEspace :: ReturnCode Source

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)

Eq CompOption
Num CompOption
Show CompOption
Bits CompOption
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)

Eq ExecOption
Num ExecOption
Show ExecOption
Bits ExecOption
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)