Safe Haskell	None
Language	Haskell2010

Text.Regex.Pcre2.Unsafe

Contents

Options
Types

Description

These items are unsafe for one reason or another, and are sequestered here to require the user to do an extra import to get them.

Chief among them is the callout interface: these options and associated datatypes may be used to register effectful callbacks, sometimes referred to as callouts in the PCRE2 API, for regex compilation, matching, and substitution. We include them here for completeness and use them to implement unit tests for this library; for ordinary use, however, seek other means to accomplish whatever is needed (such as accreting effects with optics), since they carry all the problems of unsafePerformIO. See the C API docs for more information.

Synopsis

data Option
- = BadEscapeIsLiteral
- | UnsafeCompileRecGuard (Int -> IO Bool)
- | UnsafeCallout (CalloutInfo -> IO CalloutResult)
- | AutoCallout
- | UnsafeSubCallout (SubCalloutInfo -> IO SubCalloutResult)
data CalloutInfo = CalloutInfo {
- calloutIndex :: CalloutIndex
- calloutCaptures :: NonEmpty (Maybe Text)
- calloutSubject :: Text
- calloutMark :: Maybe Text
- calloutIsFirst :: Bool
- calloutBacktracked :: Bool
}
data CalloutIndex
- = CalloutNumber Int
- | CalloutName Text
- | CalloutAuto Int Int
data CalloutResult
data SubCalloutInfo = SubCalloutInfo {
- subCalloutSubsCount :: Int
- subCalloutCaptures :: NonEmpty (Maybe Text)
- subCalloutSubject :: Text
- subCalloutReplacement :: Text
}
data SubCalloutResult
- = SubCalloutAccept
- | SubCalloutSkip
- | SubCalloutAbort

Options

data Option Source #

A Monoid representing nearly every facility PCRE2 presents for tweaking the behavior of regex compilation and execution.

All library functions that take options have the suffix Opt in their names; for each of them, there's also a non-Opt convenience function that simply has the (unexported) mempty option. For many uses, options won't be needed.

Some options can be enabled by special character sequences in the pattern as an alternative to specifying them as an Option. See Caseless for example.

Most options are exported in Text.Regex.Pcre2. The callout interface is found in Text.Regex.Pcre2.Unsafe.

Documentation is scant here. For more complete, accurate information, including discussions of corner cases arising from specific combinations of options and pattern items, please see the C API documentation.

Constructors

BadEscapeIsLiteral	Do not throw an error for unrecognized or malformed escapes. "This is a dangerous option."
UnsafeCompileRecGuard (Int -> IO Bool)	Run the given guard on every new descent into a level of parentheses, passing the current depth as argument. Returning `False` aborts pattern compilation with an exception. Multiples of this option before the rightmost are ignored. NOTE: Currently (PCRE2 version 10.39) patterns seem to be compiled in two passes, both times triggering the recursion guard. Also, it is triggered at the beginning of the pattern, passing 0. None of this is documented; expect the unexpected in the presence of side effects!
UnsafeCallout (CalloutInfo -> IO CalloutResult)	Run the given callout at every callout point (see the docs for more info). Multiples of this option before the rightmost are ignored.
AutoCallout	Run callout for every pattern item. Only relevant if a callout is set.
UnsafeSubCallout (SubCalloutInfo -> IO SubCalloutResult)	Run the given callout on every substitution. This is at most once unless `SubGlobal` is set. Multiples of this option before the rightmost are ignored.

Instances

Instances details

Semigroup Option Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods (<>) :: Option -> Option -> Option # sconcat :: NonEmpty Option -> Option # stimes :: Integral b => b -> Option -> Option #
Monoid Option Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods mempty :: Option # mappend :: Option -> Option -> Option # mconcat :: [Option] -> Option #

Types

data CalloutInfo Source #

Input for user-defined callouts.

Constructors

CalloutInfo

Fields

calloutIndex :: CalloutIndex
The index of which callout point we're on.
calloutCaptures :: NonEmpty (Maybe Text)
The captures that have been set so far.
calloutSubject :: Text
The original subject.
calloutMark :: Maybe Text
The name of the most recently passed (*MARK), (*PRUNE), or (*THEN), if any.
calloutIsFirst :: Bool
Is this the first callout after the start of matching?
calloutBacktracked :: Bool
Has a backtrack occurred since the previous callout, or the beginning of matching if no previous callouts?

Instances

Instances details

Eq CalloutInfo Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods (==) :: CalloutInfo -> CalloutInfo -> Bool # (/=) :: CalloutInfo -> CalloutInfo -> Bool #
Show CalloutInfo Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods showsPrec :: Int -> CalloutInfo -> ShowS # show :: CalloutInfo -> String # showList :: [CalloutInfo] -> ShowS #

data CalloutIndex Source #

What caused the callout.

Constructors

CalloutNumber Int	Numerical callout.
CalloutName Text	String callout.
CalloutAuto Int Int	The item located at this half-open range of offsets within the pattern. See `AutoCallout`.

Instances

Instances details

Eq CalloutIndex Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods (==) :: CalloutIndex -> CalloutIndex -> Bool # (/=) :: CalloutIndex -> CalloutIndex -> Bool #
Show CalloutIndex Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods showsPrec :: Int -> CalloutIndex -> ShowS # show :: CalloutIndex -> String # showList :: [CalloutIndex] -> ShowS #

data CalloutResult Source #

Callout functions return one of these values, which dictates what happens next in the match.

Constructors

CalloutProceed	Keep going.
CalloutNoMatchHere	Fail the current capture, but not the whole match. For example, backtracking may occur.
CalloutNoMatch	Fail the whole match.

Instances

Instances details

Eq CalloutResult Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods (==) :: CalloutResult -> CalloutResult -> Bool # (/=) :: CalloutResult -> CalloutResult -> Bool #
Show CalloutResult Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods showsPrec :: Int -> CalloutResult -> ShowS # show :: CalloutResult -> String # showList :: [CalloutResult] -> ShowS #

data SubCalloutInfo Source #

Input for user-defined substitution callouts.

Constructors

SubCalloutInfo
Fields subCalloutSubsCount :: Int The 1-based index of which substitution we're on. Only goes past 1 during global substitutions. subCalloutCaptures :: NonEmpty (Maybe Text) The captures that have been set so far. subCalloutSubject :: Text The original subject. subCalloutReplacement :: Text The replacement.

Instances

Instances details

Eq SubCalloutInfo Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods (==) :: SubCalloutInfo -> SubCalloutInfo -> Bool # (/=) :: SubCalloutInfo -> SubCalloutInfo -> Bool #
Show SubCalloutInfo Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods showsPrec :: Int -> SubCalloutInfo -> ShowS # show :: SubCalloutInfo -> String # showList :: [SubCalloutInfo] -> ShowS #

data SubCalloutResult Source #

Substitution callout functions return one of these values, which dictates what happens next in the substitution.

Constructors

SubCalloutAccept	Succeed, and keep going if in global mode.
SubCalloutSkip	Do not perform this substitution, but keep going if in global mode.
SubCalloutAbort	Do not perform this or any subsequent substitutions.

Instances

Instances details

Eq SubCalloutResult Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods (==) :: SubCalloutResult -> SubCalloutResult -> Bool # (/=) :: SubCalloutResult -> SubCalloutResult -> Bool #
Show SubCalloutResult Source #
Instance details Defined in Text.Regex.Pcre2.Internal Methods showsPrec :: Int -> SubCalloutResult -> ShowS # show :: SubCalloutResult -> String # showList :: [SubCalloutResult] -> ShowS #