gi-glib-2.0.30: GLib bindings

Copyright | Will Thompson and Iñaki García Etxebarria
License | LGPL-2.1
Maintainer | Iñaki García Etxebarria
Safe Haskell | Safe-Inferred
Language | Haskell2010

GI.GLib.Structs.Regex

Contents

- Exported types
- Methods
  - checkReplacement
  - errorQuark
  - escapeNul
  - escapeString
  - getCaptureCount
  - getCompileFlags
  - getHasCrOrLf
  - getMatchFlags
  - getMaxBackref
  - getMaxLookbehind
  - getPattern
  - getStringNumber
  - match
  - matchAll
  - matchAllFull
  - matchFull
  - matchSimple
  - new
  - ref
  - replace
  - replaceEval
  - replaceLiteral
  - split
  - splitFull
  - splitSimple
  - unref

Description

A `GRegex` is the "compiled" form of a regular expression pattern.

`GRegex` implements regular expression pattern matching using syntax and semantics similar to Perl regular expression. See the PCRE documentation) for the syntax definition.

Some functions accept a `startPosition` argument, setting it differs from just passing over a shortened string and setting `RegexMatchFlagsNotbol` in the case of a pattern that begins with any kind of lookbehind assertion. For example, consider the pattern "\Biss\B" which finds occurrences of "iss" in the middle of words. ("\B" matches only if the current position in the subject is not a word boundary.) When applied to the string "Mississipi" from the fourth byte, namely "issipi", it does not match, because "\B" is always false at the start of the subject, which is deemed to be a word boundary. However, if the entire string is passed , but with `startPosition` set to 4, it finds the second occurrence of "iss" because it is able to look behind the starting point to discover that it is preceded by a letter.

Note that, unless you set the `RegexCompileFlagsRaw` flag, all the strings passed to these functions must be encoded in UTF-8. The lengths and the positions inside the strings are in bytes and not in characters, so, for instance, "\xc3\xa0" (i.e. "à") is two bytes long but it is treated as a single character. If you set `RegexCompileFlagsRaw` the strings can be non-valid UTF-8 strings and a byte is treated as a character, so "\xc3\xa0" is two bytes and two characters long.

When matching a pattern, "\n" matches only against a "\n" character in the string, and "\r" matches only a "\r" character. To match any newline sequence use "\R". This particular group matches either the two-character sequence CR + LF ("\r\n"), or one of the single characters LF (linefeed, U+000A, "\n"), VT vertical tab, U+000B, "\v"), FF (formfeed, U+000C, "\f"), CR (carriage return, U+000D, "\r"), NEL (next line, U+0085), LS (line separator, U+2028), or PS (paragraph separator, U+2029).

The behaviour of the dot, circumflex, and dollar metacharacters are affected by newline characters, the default is to recognize any newline character (the same characters recognized by "\R"). This can be changed with `G_REGEX_NEWLINE_CR`, `G_REGEX_NEWLINE_LF` and `G_REGEX_NEWLINE_CRLF` compile options, and with `G_REGEX_MATCH_NEWLINE_ANY`, `G_REGEX_MATCH_NEWLINE_CR`, `G_REGEX_MATCH_NEWLINE_LF` and `G_REGEX_MATCH_NEWLINE_CRLF` match options. These settings are also relevant when compiling a pattern if `G_REGEX_EXTENDED` is set, and an unescaped "#" outside a character class is encountered. This indicates a comment that lasts until after the next newline.

Creating and manipulating the same `GRegex` structure from different threads is not a problem as `GRegex` does not modify its internal state between creation and destruction, on the other hand `GMatchInfo` is not threadsafe.

The regular expressions low-level functionalities are obtained through the excellent PCRE library written by Philip Hazel.

Since: 2.14

Synopsis

- newtype Regex = Regex (ManagedPtr Regex)
- regexCheckReplacement :: (HasCallStack, MonadIO m) => Text -> m Bool
- regexErrorQuark :: (HasCallStack, MonadIO m) => m Word32
- regexEscapeNul :: (HasCallStack, MonadIO m) => Text -> Int32 -> m Text
- regexEscapeString :: (HasCallStack, MonadIO m) => Text -> Int32 -> m Text
- regexGetCaptureCount :: (HasCallStack, MonadIO m) => Regex -> m Int32
- regexGetCompileFlags :: (HasCallStack, MonadIO m) => Regex -> m [RegexCompileFlags]
- regexGetHasCrOrLf :: (HasCallStack, MonadIO m) => Regex -> m Bool
- regexGetMatchFlags :: (HasCallStack, MonadIO m) => Regex -> m [RegexMatchFlags]
- regexGetMaxBackref :: (HasCallStack, MonadIO m) => Regex -> m Int32
- regexGetMaxLookbehind :: (HasCallStack, MonadIO m) => Regex -> m Int32
- regexGetPattern :: (HasCallStack, MonadIO m) => Regex -> m Text
- regexGetStringNumber :: (HasCallStack, MonadIO m) => Regex -> Text -> m Int32
- regexMatch :: (HasCallStack, MonadIO m) => Regex -> Text -> [RegexMatchFlags] -> m (Bool, MatchInfo)
- regexMatchAll :: (HasCallStack, MonadIO m) => Regex -> Text -> [RegexMatchFlags] -> m (Bool, MatchInfo)
- regexMatchAllFull :: (HasCallStack, MonadIO m) => Regex -> [Text] -> Int32 -> [RegexMatchFlags] -> m MatchInfo
- regexMatchFull :: (HasCallStack, MonadIO m) => Regex -> [Text] -> Int32 -> [RegexMatchFlags] -> m MatchInfo
- regexMatchSimple :: (HasCallStack, MonadIO m) => Text -> Text -> [RegexCompileFlags] -> [RegexMatchFlags] -> m Bool
- regexNew :: (HasCallStack, MonadIO m) => Text -> [RegexCompileFlags] -> [RegexMatchFlags] -> m (Maybe Regex)
- regexRef :: (HasCallStack, MonadIO m) => Regex -> m Regex
- regexReplace :: (HasCallStack, MonadIO m) => Regex -> [Text] -> Int32 -> Text -> [RegexMatchFlags] -> m Text
- regexReplaceEval :: (HasCallStack, MonadIO m) => Regex -> [Text] -> Int32 -> [RegexMatchFlags] -> RegexEvalCallback -> m Text
- regexReplaceLiteral :: (HasCallStack, MonadIO m) => Regex -> [Text] -> Int32 -> Text -> [RegexMatchFlags] -> m Text
- regexSplit :: (HasCallStack, MonadIO m) => Regex -> Text -> [RegexMatchFlags] -> m [Text]
- regexSplitFull :: (HasCallStack, MonadIO m) => Regex -> [Text] -> Int32 -> [RegexMatchFlags] -> Int32 -> m [Text]
- regexSplitSimple :: (HasCallStack, MonadIO m) => Text -> Text -> [RegexCompileFlags] -> [RegexMatchFlags] -> m [Text]
- regexUnref :: (HasCallStack, MonadIO m) => Regex -> m ()

# Exported types

newtype Regex Source #

Memory-managed wrapper type.

Constructors

Regex (ManagedPtr Regex) |

#### Instances

Instances details

Eq Regex Source # |
Instance details Defined in GI.GLib.Structs.Regex Methods (==) :: Regex -> Regex -> Bool Source # (/=) :: Regex -> Regex -> Bool Source #
GBoxed Regex Source # |
Instance details Defined in GI.GLib.Structs.Regex
ManagedPtrNewtype Regex Source # |
Instance details Defined in GI.GLib.Structs.Regex Methods toManagedPtr :: Regex -> ManagedPtr Regex Source #
TypedObject Regex Source # |
Instance details Defined in GI.GLib.Structs.Regex Methods glibType :: IO GType Source #
HasParentTypes Regex Source # |
Instance details Defined in GI.GLib.Structs.Regex
IsGValue (Maybe Regex) Source # | Convert `Regex` to and from `GValue`. See `toGValue` and `fromGValue`.
Instance details Defined in GI.GLib.Structs.Regex Methods gvalueGType_ :: IO GType Source # gvalueSet_ :: Ptr GValue -> Maybe Regex -> IO () Source # gvalueGet_ :: Ptr GValue -> IO (Maybe Regex) Source #
type ParentTypes Regex Source # |
Instance details Defined in GI.GLib.Structs.Regex type ParentTypes Regex = '[] :: [Type]

# Methods

### Click to display all available methods, including inherited ones

Expand

#### Methods

match, matchAll, matchAllFull, matchFull, ref, replace, replaceEval, replaceLiteral, split, splitFull, unref.

#### Getters

getCaptureCount, getCompileFlags, getHasCrOrLf, getMatchFlags, getMaxBackref, getMaxLookbehind, getPattern, getStringNumber.

#### Setters

None.

## checkReplacement

regexCheckReplacement Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Text | `replacement`: the replacement string
-> m Bool | (Can throw `GError`)

Checks whether `replacement` is a valid replacement string (see `regexReplace`), i.e. that all escape sequences in it are valid.

If `hasReferences` is not `Nothing` then `replacement` is checked for pattern references. For instance, replacement text 'foo\n' does not contain references and may be evaluated without information about actual match, but '\0\1' (whole match followed by first subpattern) requires valid `MatchInfo` object.

Since: 2.14

## errorQuark

regexErrorQuark :: (HasCallStack, MonadIO m) => m Word32 Source #

No description available in the introspection data.

## escapeNul

regexEscapeNul Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Text | `string`: the string to escape
-> Int32 | `length`: the length of `string`
-> m Text | Returns: a newly-allocated escaped string

Escapes the nul characters in `string` to "\x00". It can be used to compile a regex with embedded nul characters.

For completeness, `length` can be -1 for a nul-terminated string. In this case the output string will be of course equal to `string`.

Since: 2.30

## escapeString

regexEscapeString Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Text | `string`: the string to escape
-> Int32 | `length`: the length of `string`, in bytes, or -1 if `string` is nul-terminated
-> m Text | Returns: a newly-allocated escaped string

Escapes the special characters used for regular expressions in `string`, for instance "a.b*c" becomes "a\.b\*c". This function is useful to dynamically generate regular expressions.

`string` can contain nul characters that are replaced with "\0", in this case remember to specify the correct length of `string` in `length`.

Since: 2.14

## getCaptureCount

regexGetCaptureCount Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex`
-> m Int32 | Returns: the number of capturing subpatterns

Returns the number of capturing subpatterns in the pattern.

Since: 2.14

## getCompileFlags

regexGetCompileFlags Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex`
-> m [RegexCompileFlags] | Returns: flags from `RegexCompileFlags`

Returns the compile options that `regex` was created with.

Depending on the version of PCRE that is used, this may or may not include flags set by option expressions such as `(?i)` found at the top-level within the compiled pattern.

Since: 2.26

## getHasCrOrLf

regexGetHasCrOrLf Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure
-> m Bool | Returns: `True` if the pattern contains explicit CR or LF references

Checks whether the pattern contains explicit CR or LF references.

Since: 2.34

## getMatchFlags

regexGetMatchFlags Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex`
-> m [RegexMatchFlags] | Returns: flags from `RegexMatchFlags`

Returns the match options that `regex` was created with.

Since: 2.26

## getMaxBackref

regexGetMaxBackref Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex`
-> m Int32 | Returns: the number of the highest back reference

Returns the number of the highest back reference in the pattern, or 0 if the pattern does not contain back references.

Since: 2.14

## getMaxLookbehind

regexGetMaxLookbehind Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure
-> m Int32 | Returns: the number of characters in the longest lookbehind assertion.

Gets the number of characters in the longest lookbehind assertion in the pattern. This information is useful when doing multi-segment matching using the partial matching facilities.

Since: 2.38

## getPattern

regexGetPattern Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure
-> m Text | Returns: the pattern of `regex`

Gets the pattern string associated with `regex`, i.e. a copy of the string passed to `regexNew`.

Since: 2.14

## getStringNumber

regexGetStringNumber Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: `Regex` structure
-> Text | `name`: name of the subexpression
-> m Int32 | Returns: The number of the subexpression or -1 if `name` does not exists

Retrieves the number of the subexpression named `name`.

Since: 2.14

## match

regexMatch Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure from `regexNew`
-> Text | `string`: the string to scan for matches
-> [RegexMatchFlags] | `matchOptions`: match options
-> m (Bool, MatchInfo) | Returns: `True` is the string matched, `False` otherwise

Scans for a match in `string` for the pattern in `regex`. The `matchOptions` are combined with the match options specified when the `regex` structure was created, letting you have more flexibility in reusing `Regex` structures.

Unless `RegexCompileFlagsRaw` is specified in the options, `string` must be valid UTF-8.

A `MatchInfo` structure, used to get information on the match, is stored in `matchInfo` if not `Nothing`. Note that if `matchInfo` is not `Nothing` then it is created even if the function returns `False`, i.e. you must free it regardless if regular expression actually matched.

To retrieve all the non-overlapping matches of the pattern in string you can use `matchInfoNext`.

### C code

    static void
    print_uppercase_words (const gchar *string)
    {
      // Print all uppercase-only words.
      GRegex *regex;
      GMatchInfo *match_info;

      regex = g_regex_new ("[A-Z]+", G_REGEX_DEFAULT, G_REGEX_MATCH_DEFAULT, NULL);
      g_regex_match (regex, string, 0, &match_info);
      while (g_match_info_matches (match_info))
        {
          gchar *word = g_match_info_fetch (match_info, 0);
          g_print ("Found: %s\n", word);
          g_free (word);
          g_match_info_next (match_info, NULL);
        }
      g_match_info_free (match_info);
      g_regex_unref (regex);
    }

`string` is not copied and is used in `MatchInfo` internally. If you use any `MatchInfo` method (except `matchInfoFree`) after freeing or modifying `string` then the behaviour is undefined.

Since: 2.14

## matchAll

regexMatchAll Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure from `regexNew`
-> Text | `string`: the string to scan for matches
-> [RegexMatchFlags] | `matchOptions`: match options
-> m (Bool, MatchInfo) | Returns: `True` is the string matched, `False` otherwise

Using the standard algorithm for regular expression matching only the longest match in the string is retrieved. This function uses a different algorithm so it can retrieve all the possible matches. For more documentation see `regexMatchAllFull`.

A `MatchInfo` structure, used to get information on the match, is stored in `matchInfo` if not `Nothing`. Note that if `matchInfo` is not `Nothing` then it is created even if the function returns `False`, i.e. you must free it regardless if regular expression actually matched.

`string` is not copied and is used in `MatchInfo` internally. If you use any `MatchInfo` method (except `matchInfoFree`) after freeing or modifying `string` then the behaviour is undefined.

Since: 2.14

## matchAllFull

regexMatchAllFull Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure from `regexNew`
-> [Text] | `string`: the string to scan for matches
-> Int32 | `startPosition`: starting index of the string to match, in bytes
-> [RegexMatchFlags] | `matchOptions`: match options
-> m MatchInfo | (Can throw `GError`)

Using the standard algorithm for regular expression matching only the longest match in the `string` is retrieved, it is not possible to obtain all the available matches. For instance matching `"<a> <b> <c>"` against the pattern `"<.*>"` you get `"<a> <b> <c>"`.

This function uses a different algorithm (called DFA, i.e. deterministic finite automaton), so it can retrieve all the possible matches, all starting at the same point in the string. For instance matching `"<a> <b> <c>"` against the pattern `"<.*>"` you would obtain three matches: `"<a> <b> <c>"`, `"<a> <b>"` and `"<a>"`.

The number of matched strings is retrieved using `matchInfoGetMatchCount`. To obtain the matched strings and their position you can use, respectively, `matchInfoFetch` and `matchInfoFetchPos`. Note that the strings are returned in reverse order of length; that is, the longest matching string is given first.

Note that the DFA algorithm is slower than the standard one and it is not able to capture substrings, so backreferences do not work.

Setting `startPosition` differs from just passing over a shortened string and setting `RegexMatchFlagsNotbol` in the case of a pattern that begins with any kind of lookbehind assertion, such as "\b".

Unless `RegexCompileFlagsRaw` is specified in the options, `string` must be valid UTF-8.

A `MatchInfo` structure, used to get information on the match, is stored in `matchInfo` if not `Nothing`. Note that if `matchInfo` is not `Nothing` then it is created even if the function returns `False`, i.e. you must free it regardless if regular expression actually matched.

`string` is not copied and is used in `MatchInfo` internally. If you use any `MatchInfo` method (except `matchInfoFree`) after freeing or modifying `string` then the behaviour is undefined.

Since: 2.14

## matchFull

regexMatchFull Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure from `regexNew`
-> [Text] | `string`: the string to scan for matches
-> Int32 | `startPosition`: starting index of the string to match, in bytes
-> [RegexMatchFlags] | `matchOptions`: match options
-> m MatchInfo | (Can throw `GError`)

Scans for a match in `string` for the pattern in `regex`. The `matchOptions` are combined with the match options specified when the `regex` structure was created, letting you have more flexibility in reusing `Regex` structures.

Setting `startPosition` differs from just passing over a shortened string and setting `RegexMatchFlagsNotbol` in the case of a pattern that begins with any kind of lookbehind assertion, such as "\b".

Unless `RegexCompileFlagsRaw` is specified in the options, `string` must be valid UTF-8.

A `MatchInfo` structure, used to get information on the match, is stored in `matchInfo` if not `Nothing`. Note that if `matchInfo` is not `Nothing` then it is created even if the function returns `False`, i.e. you must free it regardless if regular expression actually matched.

`string` is not copied and is used in `MatchInfo` internally. If you use any `MatchInfo` method (except `matchInfoFree`) after freeing or modifying `string` then the behaviour is undefined.

To retrieve all the non-overlapping matches of the pattern in string you can use `matchInfoNext`.

### C code

    static void
    print_uppercase_words (const gchar *string)
    {
      // Print all uppercase-only words.
      GRegex *regex;
      GMatchInfo *match_info;
      GError *error = NULL;

      regex = g_regex_new ("[A-Z]+", G_REGEX_DEFAULT, G_REGEX_MATCH_DEFAULT, NULL);
      g_regex_match_full (regex, string, -1, 0, 0, &match_info, &error);
      while (g_match_info_matches (match_info))
        {
          gchar *word = g_match_info_fetch (match_info, 0);
          g_print ("Found: %s\n", word);
          g_free (word);
          g_match_info_next (match_info, &error);
        }
      g_match_info_free (match_info);
      g_regex_unref (regex);
      if (error != NULL)
        {
          g_printerr ("Error while matching: %s\n", error->message);
          g_error_free (error);
        }
    }

Since: 2.14

## matchSimple

regexMatchSimple Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Text | `pattern`: the regular expression
-> Text | `string`: the string to scan for matches
-> [RegexCompileFlags] | `compileOptions`: compile options for the regular expression, or 0
-> [RegexMatchFlags] | `matchOptions`: match options, or 0
-> m Bool | Returns: `True` if the string matched, `False` otherwise

Scans for a match in `string` for `pattern`.

This function is equivalent to `regexMatch` but it does not require to compile the pattern with `regexNew`, avoiding some lines of code when you need just to do a match without extracting substrings, capture counts, and so on.

If this function is to be called on the same `pattern` more than once, it's more efficient to compile the pattern once with `regexNew` and then use `regexMatch`.

Since: 2.14

## new

regexNew Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Text | `pattern`: the regular expression
-> [RegexCompileFlags] | `compileOptions`: compile options for the regular expression, or 0
-> [RegexMatchFlags] | `matchOptions`: match options for the regular expression, or 0
-> m (Maybe Regex) | Returns: a `Regex` structure or `Nothing` if an error occurred. Call `regexUnref` when you are done with it (Can throw `GError`)

Compiles the regular expression to an internal form, and does the initial setup of the `Regex` structure.

Since: 2.14

## ref

regexRef Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex`
-> m Regex | Returns: `regex`

Increases reference count of `regex` by 1.

Since: 2.14

## replace

regexReplace Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure
-> [Text] | `string`: the string to perform matches against
-> Int32 | `startPosition`: starting index of the string to match, in bytes
-> Text | `replacement`: text to replace each match with
-> [RegexMatchFlags] | `matchOptions`: options for the match
-> m Text | Returns: a newly allocated string containing the replacements (Can throw `GError`)

Replaces all occurrences of the pattern in `regex` with the replacement text. Backreferences of the form `\number` or `\g<number>` in the replacement text are interpolated by the number-th captured subexpression of the match, `\g<name>` refers to the captured subexpression with the given name. `\0` refers to the complete match, but `\0` followed by a number is the octal representation of a character. To include a literal `\` in the replacement, write `\\\\`.

There are also escapes that changes the case of the following text:

- \l: Convert to lower case the next character
- \u: Convert to upper case the next character
- \L: Convert to lower case till \E
- \U: Convert to upper case till \E
- \E: End case modification

If you do not need to use backreferences use `regexReplaceLiteral`.

The `replacement` string must be UTF-8 encoded even if `RegexCompileFlagsRaw` was passed to `regexNew`. If you want to use not UTF-8 encoded strings you can use `regexReplaceLiteral`.

Setting `startPosition` differs from just passing over a shortened string and setting `RegexMatchFlagsNotbol` in the case of a pattern that begins with any kind of lookbehind assertion, such as "\b".

Since: 2.14

## replaceEval

regexReplaceEval Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure from `regexNew`
-> [Text] | `string`: string to perform matches against
-> Int32 | `startPosition`: starting index of the string to match, in bytes
-> [RegexMatchFlags] | `matchOptions`: options for the match
-> RegexEvalCallback | `eval`: a function to call for each match
-> m Text | Returns: a newly allocated string containing the replacements (Can throw `GError`)

Replaces occurrences of the pattern in regex with the output of `eval` for that occurrence.

Setting `startPosition` differs from just passing over a shortened string and setting `RegexMatchFlagsNotbol` in the case of a pattern that begins with any kind of lookbehind assertion, such as "\b".

The following example uses `regexReplaceEval` to replace multiple strings at once:

### C code

    static gboolean
    eval_cb (const GMatchInfo *info,
             GString          *res,
             gpointer          data)
    {
      gchar *match;
      gchar *r;

       match = g_match_info_fetch (info, 0);
       r = g_hash_table_lookup ((GHashTable *)data, match);
       g_string_append (res, r);
       g_free (match);

       return FALSE;
    }

    ...

    GRegex *reg;
    GHashTable *h;
    gchar *res;

    h = g_hash_table_new (g_str_hash, g_str_equal);

    g_hash_table_insert (h, "1", "ONE");
    g_hash_table_insert (h, "2", "TWO");
    g_hash_table_insert (h, "3", "THREE");
    g_hash_table_insert (h, "4", "FOUR");

    reg = g_regex_new ("1|2|3|4", G_REGEX_DEFAULT, G_REGEX_MATCH_DEFAULT, NULL);
    res = g_regex_replace_eval (reg, text, -1, 0, 0, eval_cb, h, NULL);
    g_hash_table_destroy (h);

    ...

Since: 2.14

## replaceLiteral

regexReplaceLiteral Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure
-> [Text] | `string`: the string to perform matches against
-> Int32 | `startPosition`: starting index of the string to match, in bytes
-> Text | `replacement`: text to replace each match with
-> [RegexMatchFlags] | `matchOptions`: options for the match
-> m Text | Returns: a newly allocated string containing the replacements (Can throw `GError`)

Replaces all occurrences of the pattern in `regex` with the replacement text. `replacement` is replaced literally, to include backreferences use `regexReplace`.

Setting `startPosition` differs from just passing over a shortened string and setting `RegexMatchFlagsNotbol` in the case of a pattern that begins with any kind of lookbehind assertion, such as "\b".

Since: 2.14

## split

regexSplit Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure
-> Text | `string`: the string to split with the pattern
-> [RegexMatchFlags] | `matchOptions`: match time option flags
-> m [Text] | Returns: a `Nothing`-terminated gchar ** array. Free it using `strfreev`

Breaks the string on the pattern, and returns an array of the tokens. If the pattern contains capturing parentheses, then the text for each of the substrings will also be returned. If the pattern does not match anywhere in the string, then the whole string is returned as the first token.

As a special case, the result of splitting the empty string "" is an empty vector, not a vector containing a single string. The reason for this special case is that being able to represent an empty vector is typically more useful than consistent handling of empty elements. If you do need to represent empty elements, you'll need to check for the empty string before calling this function.

A pattern that can match empty strings splits `string` into separate characters wherever it matches the empty string between characters. For example splitting "ab c" using as a separator "\s*", you will get "a", "b" and "c".

Since: 2.14

## splitFull

regexSplitFull Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex` structure
-> [Text] | `string`: the string to split with the pattern
-> Int32 | `startPosition`: starting index of the string to match, in bytes
-> [RegexMatchFlags] | `matchOptions`: match time option flags
-> Int32 | `maxTokens`: the maximum number of tokens to split `string` into. If this is less than 1, the string is split completely
-> m [Text] | Returns: a `Nothing`-terminated gchar ** array. Free it using `strfreev` (Can throw `GError`)

Breaks the string on the pattern, and returns an array of the tokens. If the pattern contains capturing parentheses, then the text for each of the substrings will also be returned. If the pattern does not match anywhere in the string, then the whole string is returned as the first token.

As a special case, the result of splitting the empty string "" is an empty vector, not a vector containing a single string. The reason for this special case is that being able to represent an empty vector is typically more useful than consistent handling of empty elements. If you do need to represent empty elements, you'll need to check for the empty string before calling this function.

A pattern that can match empty strings splits `string` into separate characters wherever it matches the empty string between characters. For example splitting "ab c" using as a separator "\s*", you will get "a", "b" and "c".

Setting `startPosition` differs from just passing over a shortened string and setting `RegexMatchFlagsNotbol` in the case of a pattern that begins with any kind of lookbehind assertion, such as "\b".

Since: 2.14

## splitSimple

regexSplitSimple Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Text | `pattern`: the regular expression
-> Text | `string`: the string to scan for matches
-> [RegexCompileFlags] | `compileOptions`: compile options for the regular expression, or 0
-> [RegexMatchFlags] | `matchOptions`: match options, or 0
-> m [Text] | Returns: a `Nothing`-terminated array of strings. Free it using `strfreev`

Breaks the string on the pattern, and returns an array of the tokens. If the pattern contains capturing parentheses, then the text for each of the substrings will also be returned. If the pattern does not match anywhere in the string, then the whole string is returned as the first token.

This function is equivalent to `regexSplit` but it does not require to compile the pattern with `regexNew`, avoiding some lines of code when you need just to do a split without extracting substrings, capture counts, and so on.

If this function is to be called on the same `pattern` more than once, it's more efficient to compile the pattern once with `regexNew` and then use `regexSplit`.

As a special case, the result of splitting the empty string "" is an empty vector, not a vector containing a single string. The reason for this special case is that being able to represent an empty vector is typically more useful than consistent handling of empty elements. If you do need to represent empty elements, you'll need to check for the empty string before calling this function.

A pattern that can match empty strings splits `string` into separate characters wherever it matches the empty string between characters. For example splitting "ab c" using as a separator "\s*", you will get "a", "b" and "c".

Since: 2.14

## unref

regexUnref Source #

Arguments

:: (HasCallStack, MonadIO m) |
=> Regex | `regex`: a `Regex`
-> m () |

Decreases reference count of `regex` by 1. When reference count drops to zero, it frees all the memory associated with the regex structure.

Since: 2.14