Description
The g_regex_*() functions implement regular
expression pattern matching using syntax and semantics similar to
Perl regular expression.
Some functions accept a start_position
argument, setting it differs
from just passing over a shortened string and setting G_REGEX_MATCH_NOTBOL
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
start_position
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 G_REGEX_RAW 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 G_REGEX_RAW 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.
When setting the G_REGEX_JAVASCRIPT_COMPAT flag, pattern syntax and pattern
matching is changed to be compatible with the way that regular expressions
work in JavaScript. More precisely, a lonely ']' character in the pattern
is a syntax error; the '\x' escape only allows 0 to 2 hexadecimal digits, and
you must use the '\u' escape sequence with 4 hex digits to specify a unicode
codepoint instead of '\x' or 'x{....}'. If '\x' or '\u' are not followed by
the specified number of hex digits, they match 'x' and 'u' literally; also
'\U' always matches 'U' instead of being an error in the pattern. Finally,
pattern matching is modified so that back references to an unset subpattern
group produces a match with the empty string instead of an error. See
pcreapi(3) for more information.
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.
Functions
g_regex_ref ()
GRegex *
g_regex_ref (GRegex *regex);
Increases reference count of regex
by 1.
Since: 2.14
g_regex_unref ()
void
g_regex_unref (GRegex *regex);
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
g_regex_get_pattern ()
const gchar *
g_regex_get_pattern (const GRegex *regex);
Gets the pattern string associated with regex
, i.e. a copy of
the string passed to g_regex_new().
Returns
the pattern of regex
Since: 2.14
g_regex_get_max_backref ()
gint
g_regex_get_max_backref (const GRegex *regex);
Returns the number of the highest back reference
in the pattern, or 0 if the pattern does not contain
back references.
Returns
the number of the highest back reference
Since: 2.14
g_regex_get_capture_count ()
gint
g_regex_get_capture_count (const GRegex *regex);
Returns the number of capturing subpatterns in the pattern.
Returns
the number of capturing subpatterns
Since: 2.14
g_regex_get_has_cr_or_lf ()
gboolean
g_regex_get_has_cr_or_lf (const GRegex *regex);
Checks whether the pattern contains explicit CR or LF references.
Returns
TRUE if the pattern contains explicit CR or LF references
Since: 2.34
g_regex_get_max_lookbehind ()
gint
g_regex_get_max_lookbehind (const GRegex *regex);
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.
Returns
the number of characters in the longest lookbehind assertion.
Since: 2.38
g_regex_get_string_number ()
gint
g_regex_get_string_number (const GRegex *regex,
const gchar *name);
Retrieves the number of the subexpression named name
.
Returns
The number of the subexpression or -1 if name
does not exists
Since: 2.14
g_regex_get_compile_flags ()
GRegexCompileFlags
g_regex_get_compile_flags (const GRegex *regex);
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
g_regex_get_match_flags ()
GRegexMatchFlags
g_regex_get_match_flags (const GRegex *regex);
Returns the match options that regex
was created with.
Since: 2.26
g_regex_escape_string ()
gchar *
g_regex_escape_string (const gchar *string,
gint length);
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
.
Returns
a newly-allocated escaped string
Since: 2.14
g_regex_escape_nul ()
gchar *
g_regex_escape_nul (const gchar *string,
gint length);
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
.
Returns
a newly-allocated escaped string
Since: 2.30
g_regex_match_simple ()
gboolean
g_regex_match_simple (const gchar *pattern,
const gchar *string,
GRegexCompileFlags compile_options,
GRegexMatchFlags match_options);
Scans for a match in string
for pattern
.
This function is equivalent to g_regex_match() but it does not
require to compile the pattern with g_regex_new(), 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
g_regex_new() and then use g_regex_match().
Returns
TRUE if the string matched, FALSE otherwise
Since: 2.14
g_regex_match ()
gboolean
g_regex_match (const GRegex *regex,
const gchar *string,
GRegexMatchFlags match_options,
GMatchInfo **match_info);
Scans for a match in string
for the pattern in regex
.
The match_options
are combined with the match options specified
when the regex
structure was created, letting you have more
flexibility in reusing GRegex structures.
Unless G_REGEX_RAW is specified in the options, string
must be valid UTF-8.
A GMatchInfo structure, used to get information on the match,
is stored in match_info
if not NULL. Note that if match_info
is not NULL 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 g_match_info_next().
string
is not copied and is used in GMatchInfo internally. If
you use any GMatchInfo method (except g_match_info_free()) after
freeing or modifying string
then the behaviour is undefined.
Returns
TRUE is the string matched, FALSE otherwise
Since: 2.14
g_regex_match_full ()
gboolean
g_regex_match_full (const GRegex *regex,
const gchar *string,
gssize string_len,
gint start_position,
GRegexMatchFlags match_options,
GMatchInfo **match_info,
GError **error);
Scans for a match in string
for the pattern in regex
.
The match_options
are combined with the match options specified
when the regex
structure was created, letting you have more
flexibility in reusing GRegex structures.
Setting start_position
differs from just passing over a shortened
string and setting G_REGEX_MATCH_NOTBOL in the case of a pattern
that begins with any kind of lookbehind assertion, such as "\b".
Unless G_REGEX_RAW is specified in the options, string
must be valid UTF-8.
A GMatchInfo structure, used to get information on the match, is
stored in match_info
if not NULL. Note that if match_info
is
not NULL 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 GMatchInfo internally. If
you use any GMatchInfo method (except g_match_info_free()) 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 g_match_info_next().
Returns
TRUE is the string matched, FALSE otherwise
Since: 2.14
g_regex_match_all ()
gboolean
g_regex_match_all (const GRegex *regex,
const gchar *string,
GRegexMatchFlags match_options,
GMatchInfo **match_info);
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 g_regex_match_all_full().
A GMatchInfo structure, used to get information on the match, is
stored in match_info
if not NULL. Note that if match_info
is
not NULL 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 GMatchInfo internally. If
you use any GMatchInfo method (except g_match_info_free()) after
freeing or modifying string
then the behaviour is undefined.
Returns
TRUE is the string matched, FALSE otherwise
Since: 2.14
g_regex_match_all_full ()
gboolean
g_regex_match_all_full (const GRegex *regex,
const gchar *string,
gssize string_len,
gint start_position,
GRegexMatchFlags match_options,
GMatchInfo **match_info,
GError **error);
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
g_match_info_get_match_count(). To obtain the matched strings and
their position you can use, respectively, g_match_info_fetch() and
g_match_info_fetch_pos(). 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 start_position
differs from just passing over a shortened
string and setting G_REGEX_MATCH_NOTBOL in the case of a pattern
that begins with any kind of lookbehind assertion, such as "\b".
Unless G_REGEX_RAW is specified in the options, string
must be valid UTF-8.
A GMatchInfo structure, used to get information on the match, is
stored in match_info
if not NULL. Note that if match_info
is
not NULL 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 GMatchInfo internally. If
you use any GMatchInfo method (except g_match_info_free()) after
freeing or modifying string
then the behaviour is undefined.
Returns
TRUE is the string matched, FALSE otherwise
Since: 2.14
g_regex_split_simple ()
gchar **
g_regex_split_simple (const gchar *pattern,
const gchar *string,
GRegexCompileFlags compile_options,
GRegexMatchFlags match_options);
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 g_regex_split() but it does
not require to compile the pattern with g_regex_new(), 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
g_regex_new() and then use g_regex_split().
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".
Returns
a NULL-terminated array of strings. Free
it using g_strfreev().
[transfer full]
Since: 2.14
g_regex_split ()
gchar **
g_regex_split (const GRegex *regex,
const gchar *string,
GRegexMatchFlags match_options);
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".
Returns
a NULL-terminated gchar ** array. Free
it using g_strfreev().
[transfer full]
Since: 2.14
g_regex_split_full ()
gchar **
g_regex_split_full (const GRegex *regex,
const gchar *string,
gssize string_len,
gint start_position,
GRegexMatchFlags match_options,
gint max_tokens,
GError **error);
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 start_position
differs from just passing over a shortened
string and setting G_REGEX_MATCH_NOTBOL in the case of a pattern
that begins with any kind of lookbehind assertion, such as "\b".
Returns
a NULL-terminated gchar ** array. Free
it using g_strfreev().
[transfer full]
Since: 2.14
g_regex_replace ()
gchar *
g_regex_replace (const GRegex *regex,
const gchar *string,
gssize string_len,
gint start_position,
const gchar *replacement,
GRegexMatchFlags match_options,
GError **error);
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 g_regex_replace_literal().
The replacement
string must be UTF-8 encoded even if G_REGEX_RAW was
passed to g_regex_new(). If you want to use not UTF-8 encoded stings
you can use g_regex_replace_literal().
Setting start_position
differs from just passing over a shortened
string and setting G_REGEX_MATCH_NOTBOL in the case of a pattern that
begins with any kind of lookbehind assertion, such as "\b".
Returns
a newly allocated string containing the replacements
Since: 2.14
g_regex_replace_literal ()
gchar *
g_regex_replace_literal (const GRegex *regex,
const gchar *string,
gssize string_len,
gint start_position,
const gchar *replacement,
GRegexMatchFlags match_options,
GError **error);
Replaces all occurrences of the pattern in regex
with the
replacement text. replacement
is replaced literally, to
include backreferences use g_regex_replace().
Setting start_position
differs from just passing over a
shortened string and setting G_REGEX_MATCH_NOTBOL in the
case of a pattern that begins with any kind of lookbehind
assertion, such as "\b".
Returns
a newly allocated string containing the replacements
Since: 2.14
g_regex_replace_eval ()
gchar *
g_regex_replace_eval (const GRegex *regex,
const gchar *string,
gssize string_len,
gint start_position,
GRegexMatchFlags match_options,
GRegexEvalCallback eval,
gpointer user_data,
GError **error);
Replaces occurrences of the pattern in regex with the output of
eval
for that occurrence.
Setting start_position
differs from just passing over a shortened
string and setting G_REGEX_MATCH_NOTBOL in the case of a pattern
that begins with any kind of lookbehind assertion, such as "\b".
The following example uses g_regex_replace_eval() to replace multiple
strings at once:
Returns
a newly allocated string containing the replacements
Since: 2.14
g_regex_check_replacement ()
gboolean
g_regex_check_replacement (const gchar *replacement,
gboolean *has_references,
GError **error);
Checks whether replacement
is a valid replacement string
(see g_regex_replace()), i.e. that all escape sequences in
it are valid.
If has_references
is not NULL 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 GMatchInfo object.
Returns
whether replacement
is a valid replacement string
Since: 2.14
g_match_info_get_regex ()
GRegex *
g_match_info_get_regex (const GMatchInfo *match_info);
Returns GRegex object used in match_info
. It belongs to Glib
and must not be freed. Use g_regex_ref() if you need to keep it
after you free match_info
object.
Returns
GRegex object used in match_info
Since: 2.14
g_match_info_get_string ()
const gchar *
g_match_info_get_string (const GMatchInfo *match_info);
Returns the string searched with match_info
. This is the
string passed to g_regex_match() or g_regex_replace() so
you may not free it before calling this function.
Returns
the string searched with match_info
Since: 2.14
g_match_info_ref ()
GMatchInfo *
g_match_info_ref (GMatchInfo *match_info);
Increases reference count of match_info
by 1.
Since: 2.30
g_match_info_unref ()
void
g_match_info_unref (GMatchInfo *match_info);
Decreases reference count of match_info
by 1. When reference count drops
to zero, it frees all the memory associated with the match_info structure.
Since: 2.30
g_match_info_matches ()
gboolean
g_match_info_matches (const GMatchInfo *match_info);
Returns whether the previous match operation succeeded.
Returns
TRUE if the previous match operation succeeded,
FALSE otherwise
Since: 2.14
g_match_info_next ()
gboolean
g_match_info_next (GMatchInfo *match_info,
GError **error);
Scans for the next match using the same parameters of the previous
call to g_regex_match_full() or g_regex_match() that returned
match_info
.
The match is done on the string passed to the match function, so you
cannot free it before calling this function.
Returns
TRUE is the string matched, FALSE otherwise
Since: 2.14
g_match_info_get_match_count ()
gint
g_match_info_get_match_count (const GMatchInfo *match_info);
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 g_regex_match_all() or g_regex_match_all_full(), the retrieved
count is not that of the number of capturing parentheses but that of
the number of matched substrings.
Returns
Number of matched substrings, or -1 if an error occurred
Since: 2.14
g_match_info_is_partial_match ()
gboolean
g_match_info_is_partial_match (const GMatchInfo *match_info);
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
g_regex_match() or g_regex_match_full() 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
g_match_info_is_partial_match().
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.
Returns
TRUE if the match was partial, FALSE otherwise
Since: 2.14
g_match_info_expand_references ()
gchar *
g_match_info_expand_references (const GMatchInfo *match_info,
const gchar *string_to_expand,
GError **error);
Returns a new string containing the text in string_to_expand
with
references and escape sequences expanded. References refer to the last
match done with string
against regex
and have the same syntax used by
g_regex_replace().
The string_to_expand
must be UTF-8 encoded even if G_REGEX_RAW was
passed to g_regex_new().
The backreferences are extracted from the string passed to the match
function, so you cannot call this function after freeing the string.
match_info
may be NULL in which case string_to_expand
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 g_regex_check_replacement() to find out whether string_to_expand
contains references.
Returns
the expanded string, or NULL if an error occurred.
[nullable]
Since: 2.14
g_match_info_fetch ()
gchar *
g_match_info_fetch (const GMatchInfo *match_info,
gint match_num);
Retrieves the text matching the match_num
'th capturing
parentheses. 0 is the full text of the match, 1 is the first paren
set, 2 the second, and so on.
If match_num
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
g_regex_match_all() or g_regex_match_all_full(), 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.
Returns
The matched substring, or NULL if an error
occurred. You have to free the string yourself.
[nullable]
Since: 2.14
g_match_info_fetch_pos ()
gboolean
g_match_info_fetch_pos (const GMatchInfo *match_info,
gint match_num,
gint *start_pos,
gint *end_pos);
Retrieves the position in bytes of the match_num
'th capturing
parentheses. 0 is the full text of the match, 1 is the first
paren set, 2 the second, and so on.
If match_num
is a valid sub pattern but it didn't match anything
(e.g. sub pattern 1, matching "b" against "(a)?b") then start_pos
and end_pos
are set to -1 and TRUE is returned.
If the match was obtained using the DFA algorithm, that is using
g_regex_match_all() or g_regex_match_all_full(), 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.
Returns
TRUE if the position was fetched, FALSE otherwise. If
the position cannot be fetched, start_pos
and end_pos
are left
unchanged
Since: 2.14
g_match_info_fetch_named ()
gchar *
g_match_info_fetch_named (const GMatchInfo *match_info,
const gchar *name);
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.
Returns
The matched substring, or NULL if an error
occurred. You have to free the string yourself.
[nullable]
Since: 2.14
g_match_info_fetch_named_pos ()
gboolean
g_match_info_fetch_named_pos (const GMatchInfo *match_info,
const gchar *name,
gint *start_pos,
gint *end_pos);
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 start_pos
and end_pos
are set to -1 and TRUE is returned.
Returns
TRUE if the position was fetched, FALSE otherwise.
If the position cannot be fetched, start_pos
and end_pos
are left unchanged.
Since: 2.14
g_match_info_fetch_all ()
gchar **
g_match_info_fetch_all (const GMatchInfo *match_info);
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
g_regex_match_all() or g_regex_match_all_full(), 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.
Returns
a NULL-terminated array of gchar *
pointers. It must be freed using g_strfreev(). If the previous
match failed NULL is returned.
[transfer full]
Since: 2.14