regex-posix-0.95.2: Replaces/Enhances Text.Regex

Portability | non-portable (regex-base needs MPTC+FD)
Stability | experimental
Maintainer | libraries@haskell.org, textregexlazy@personal.mightyreason.com
Safe Haskell | None

Text.Regex.Posix.Sequence

Contents

- Types
- Miscellaneous
- Medium level API functions
- Compilation options

Description

This provides `String` instances for `RegexMaker` and `RegexLike` based on Text.Regex.Posix.Wrap, and a (`RegexContext` `Regex` `String` `String`) instance.

To use these instance, you would normally import Text.Regex.Posix. You only need to import this module to use the medium level API of the compile, regexec, and execute functions. All of these report error by returning Left values instead of undefined or error or fail.

Synopsis

- data Regex
- type MatchOffset = Int
- type MatchLength = Int
- data ReturnCode
- type WrapError = (ReturnCode, String)
- unusedOffset :: Int
- compile :: CompOption -> ExecOption -> Seq Char -> IO (Either WrapError Regex)
- regexec :: Regex -> Seq Char -> IO (Either WrapError (Maybe (Seq Char, Seq Char, Seq Char, [Seq Char])))
- execute :: Regex -> Seq Char -> IO (Either WrapError (Maybe (Array Int (MatchOffset, MatchLength))))
- newtype CompOption = CompOption CInt
- compBlank :: CompOption
- compExtended :: CompOption
- compIgnoreCase :: CompOption
- compNoSub :: CompOption
- compNewline :: CompOption
- newtype ExecOption = ExecOption CInt
- execBlank :: ExecOption
- execNotBOL :: ExecOption
- execNotEOL :: ExecOption

## Types

data Regex Source

A compiled regular expression.

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) |

type MatchOffset = Int

0 based index from start of source, or (-1) for unused

type MatchLength = Int

non-negative length of a match

data 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

Instances

Eq ReturnCode |
Show ReturnCode |

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.

## Miscellaneous

unusedOffset :: Int Source

## Medium level API functions

compile Source

Arguments

:: CompOption | Flags (summed together)
-> ExecOption | Flags (summed together)
-> Seq Char | The regular expression to compile (ASCII only, no null bytes)
-> IO (Either WrapError Regex) | Returns: the compiled regular expression

regexec Source

Arguments

:: Regex | Compiled regular expression
-> Seq Char | (Seq Char) to match against
-> IO (Either WrapError (Maybe (Seq Char, Seq Char, Seq Char, [Seq Char]))) | Returns: `Nothing` if the regex did not match the string, or:
       Just (everything before match,
             matched portion,
             everything after match,
             subexpression matches)

Matches a regular expression against a string

execute Source

Arguments

:: Regex | Compiled regular expression
-> Seq Char | (Seq Char) to match against
-> IO (Either WrapError (Maybe (Array Int (MatchOffset, MatchLength)))) | Returns: `Nothing` if the regex did not match the string, or:
       Just (array of offset length pairs)

Matches a regular expression against a string

## 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 |

Instances

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) |

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

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 |

Instances

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) |

execBlank :: ExecOption Source

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

execNotBOL :: ExecOption Source

execNotEOL :: ExecOption Source