Copyright | Will Thompson Iñaki García Etxebarria and Jonas Platte |
---|---|
License | LGPL-2.1 |
Maintainer | Iñaki García Etxebarria (garetxe@gmail.com) |
Safe Haskell | None |
Language | Haskell2010 |
A GMatchInfo is an opaque struct used to return information about matches.
Synopsis
- newtype MatchInfo = MatchInfo (ManagedPtr MatchInfo)
- noMatchInfo :: Maybe MatchInfo
- matchInfoExpandReferences :: (HasCallStack, MonadIO m) => MatchInfo -> Text -> m (Maybe Text)
- matchInfoFetch :: (HasCallStack, MonadIO m) => MatchInfo -> Int32 -> m (Maybe Text)
- matchInfoFetchAll :: (HasCallStack, MonadIO m) => MatchInfo -> m [Text]
- matchInfoFetchNamed :: (HasCallStack, MonadIO m) => MatchInfo -> Text -> m (Maybe Text)
- matchInfoFetchNamedPos :: (HasCallStack, MonadIO m) => MatchInfo -> Text -> m (Bool, Int32, Int32)
- matchInfoFetchPos :: (HasCallStack, MonadIO m) => MatchInfo -> Int32 -> m (Bool, Int32, Int32)
- matchInfoFree :: (HasCallStack, MonadIO m) => MatchInfo -> m ()
- matchInfoGetMatchCount :: (HasCallStack, MonadIO m) => MatchInfo -> m Int32
- matchInfoGetRegex :: (HasCallStack, MonadIO m) => MatchInfo -> m Regex
- matchInfoGetString :: (HasCallStack, MonadIO m) => MatchInfo -> m Text
- matchInfoIsPartialMatch :: (HasCallStack, MonadIO m) => MatchInfo -> m Bool
- matchInfoMatches :: (HasCallStack, MonadIO m) => MatchInfo -> m Bool
- matchInfoNext :: (HasCallStack, MonadIO m) => MatchInfo -> m ()
- matchInfoRef :: (HasCallStack, MonadIO m) => MatchInfo -> m MatchInfo
- matchInfoUnref :: (HasCallStack, MonadIO m) => MatchInfo -> m ()
Exported types
Memory-managed wrapper type.
Instances
BoxedObject MatchInfo Source # | |
Methods
expandReferences
matchInfoExpandReferences Source #
:: (HasCallStack, MonadIO m) | |
=> MatchInfo | |
-> Text |
|
-> m (Maybe Text) | Returns: the expanded string, or |
Returns a new string containing the text in stringToExpand
with
references and escape sequences expanded. References refer to the last
match done with string
against regex
and have the same syntax used by
regexReplace
.
The stringToExpand
must be UTF-8 encoded even if G_REGEX_RAW
was
passed to regexNew
.
The backreferences are extracted from the string passed to the match function, so you cannot call this function after freeing the string.
matchInfo
may be Nothing
in which case stringToExpand
must not
contain references. For instance "foo\n" does not refer to an actual
pattern and '\n' merely will be replaced with \n character,
while to expand "\0" (whole match) one needs the result of a match.
Use regexCheckReplacement
to find out whether stringToExpand
contains references.
Since: 2.14
fetch
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> Int32 |
|
-> m (Maybe Text) | Returns: The matched substring, or |
Retrieves the text matching the matchNum
'th capturing
parentheses. 0 is the full text of the match, 1 is the first paren
set, 2 the second, and so on.
If matchNum
is a valid sub pattern but it didn't match anything
(e.g. sub pattern 1, matching "b" against "(a)?b") then an empty
string is returned.
If the match was obtained using the DFA algorithm, that is using
regexMatchAll
or regexMatchAllFull
, the retrieved
string is not that of a set of parentheses but that of a matched
substring. Substrings are matched in reverse order of length, so
0 is the longest match.
The string is fetched from the string passed to the match function, so you cannot call this function after freeing the string.
Since: 2.14
fetchAll
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> m [Text] | Returns: a |
Bundles up pointers to each of the matching substrings from a match and stores them in an array of gchar pointers. The first element in the returned array is the match number 0, i.e. the entire matched text.
If a sub pattern didn't match anything (e.g. sub pattern 1, matching "b" against "(a)?b") then an empty string is inserted.
If the last match was obtained using the DFA algorithm, that is using
regexMatchAll
or regexMatchAllFull
, the retrieved
strings are not that matched by sets of parentheses but that of the
matched substring. Substrings are matched in reverse order of length,
so the first one is the longest match.
The strings are fetched from the string passed to the match function, so you cannot call this function after freeing the string.
Since: 2.14
fetchNamed
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> Text |
|
-> m (Maybe Text) | Returns: The matched substring, or |
Retrieves the text matching the capturing parentheses named name
.
If name
is a valid sub pattern name but it didn't match anything
(e.g. sub pattern "X", matching "b" against "(?P<X>a)?b")
then an empty string is returned.
The string is fetched from the string passed to the match function, so you cannot call this function after freeing the string.
Since: 2.14
fetchNamedPos
matchInfoFetchNamedPos Source #
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> Text |
|
-> m (Bool, Int32, Int32) | Returns: |
Retrieves the position in bytes of the capturing parentheses named name
.
If name
is a valid sub pattern name but it didn't match anything
(e.g. sub pattern "X", matching "b" against "(?P<X>a)?b")
then startPos
and endPos
are set to -1 and True
is returned.
Since: 2.14
fetchPos
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> Int32 |
|
-> m (Bool, Int32, Int32) | Returns: |
Retrieves the position in bytes of the matchNum
'th capturing
parentheses. 0 is the full text of the match, 1 is the first
paren set, 2 the second, and so on.
If matchNum
is a valid sub pattern but it didn't match anything
(e.g. sub pattern 1, matching "b" against "(a)?b") then startPos
and endPos
are set to -1 and True
is returned.
If the match was obtained using the DFA algorithm, that is using
regexMatchAll
or regexMatchAllFull
, the retrieved
position is not that of a set of parentheses but that of a matched
substring. Substrings are matched in reverse order of length, so
0 is the longest match.
Since: 2.14
free
:: (HasCallStack, MonadIO m) | |
=> MatchInfo | |
-> m () |
If matchInfo
is not Nothing
, calls matchInfoUnref
; otherwise does
nothing.
Since: 2.14
getMatchCount
matchInfoGetMatchCount Source #
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> m Int32 | Returns: Number of matched substrings, or -1 if an error occurred |
Retrieves the number of matched substrings (including substring 0, that is the whole matched text), so 1 is returned if the pattern has no substrings in it and 0 is returned if the match failed.
If the last match was obtained using the DFA algorithm, that is
using regexMatchAll
or regexMatchAllFull
, the retrieved
count is not that of the number of capturing parentheses but that of
the number of matched substrings.
Since: 2.14
getRegex
getString
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> m Text | Returns: the string searched with |
Returns the string searched with matchInfo
. This is the
string passed to regexMatch
or regexReplace
so
you may not free it before calling this function.
Since: 2.14
isPartialMatch
matchInfoIsPartialMatch Source #
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> m Bool |
Usually if the string passed to g_regex_match*() matches as far as
it goes, but is too short to match the entire pattern, False
is
returned. There are circumstances where it might be helpful to
distinguish this case from other cases in which there is no match.
Consider, for example, an application where a human is required to type in data for a field with specific formatting requirements. An example might be a date in the form ddmmmyy, defined by the pattern "^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$". If the application sees the user’s keystrokes one by one, and can check that what has been typed so far is potentially valid, it is able to raise an error as soon as a mistake is made.
GRegex supports the concept of partial matching by means of the
G_REGEX_MATCH_PARTIAL_SOFT
and G_REGEX_MATCH_PARTIAL_HARD
flags.
When they are used, the return code for
regexMatch
or regexMatchFull
is, as usual, True
for a complete match, False
otherwise. But, when these functions
return False
, you can check if the match was partial calling
matchInfoIsPartialMatch
.
The difference between G_REGEX_MATCH_PARTIAL_SOFT
and
G_REGEX_MATCH_PARTIAL_HARD
is that when a partial match is encountered
with G_REGEX_MATCH_PARTIAL_SOFT
, matching continues to search for a
possible complete match, while with G_REGEX_MATCH_PARTIAL_HARD
matching
stops at the partial match.
When both G_REGEX_MATCH_PARTIAL_SOFT
and G_REGEX_MATCH_PARTIAL_HARD
are set, the latter takes precedence.
There were formerly some restrictions on the pattern for partial matching. The restrictions no longer apply.
See pcrepartial(3) for more information on partial matching.
Since: 2.14
matches
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> m Bool | Returns: |
Returns whether the previous match operation succeeded.
Since: 2.14
next
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> m () | (Can throw |
Scans for the next match using the same parameters of the previous
call to regexMatchFull
or regexMatch
that returned
matchInfo
.
The match is done on the string passed to the match function, so you cannot free it before calling this function.
Since: 2.14
ref
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> m MatchInfo | Returns: |
Increases reference count of matchInfo
by 1.
Since: 2.30
unref
:: (HasCallStack, MonadIO m) | |
=> MatchInfo |
|
-> m () |
Decreases reference count of matchInfo
by 1. When reference count drops
to zero, it frees all the memory associated with the match_info structure.
Since: 2.30