<GMatchInfo>

<GMatchInfo>

Description

A GMatchInfo is an opaque struct used to return information about matches.

Functions

expand-references

(define-values (%return) (match-info:expand-references self string-to-expand))

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.

Parameters

match_info

a GMatchInfo or NULL

Passed as self

string_to_expand

the string to expand

Passed as string-to-expand

fetch

(define-values (%return) (match-info:fetch self 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.

Parameters

match_info

GMatchInfo structure

Passed as self

match_num

number of the sub expression

Passed as match-num

fetch-all

(define-values (%return) (match-info:fetch-all self))

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.

Parameters

match_info

a GMatchInfo structure

Passed as self

fetch-named

(define-values (%return) (match-info:fetch-named self 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.

Parameters

match_info

GMatchInfo structure

Passed as self

name

name of the subexpression

Passed as name

fetch-named-pos

(define-values
  (%return start-pos end-pos)
  (match-info:fetch-named-pos self name))

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.

Parameters

match_info

GMatchInfo structure

Passed as self

name

name of the subexpression

Passed as name

start_pos

pointer to location where to store the start position, or NULL

Passed as start-pos

end_pos

pointer to location where to store the end position, or NULL

Passed as end-pos

fetch-pos

(define-values
  (%return start-pos end-pos)
  (match-info:fetch-pos self match-num))

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.

Parameters

match_info

GMatchInfo structure

Passed as self

match_num

number of the sub expression

Passed as match-num

start_pos

pointer to location where to store the start position, or NULL

Passed as start-pos

end_pos

pointer to location where to store the end position, or NULL

Passed as end-pos

free

(define-values () (match-info:free self))

If match_info is not NULL, calls g_match_info_unref(); otherwise does nothing.

Parameters

match_info

a GMatchInfo, or NULL

Passed as self

get-match-count

(define-values (%return) (match-info:get-match-count self))

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.

Parameters

match_info

a GMatchInfo structure

Passed as self

get-regex

(define-values (%return) (match-info:get-regex self))

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.

Parameters

match_info

a GMatchInfo

Passed as self

get-string

(define-values (%return) (match-info:get-string self))

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.

Parameters

match_info

a GMatchInfo

Passed as self

is-partial-match?

(define-values (%return) (match-info:is-partial-match? self))

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.

Parameters

match_info

a GMatchInfo structure

Passed as self

matches?

(define-values (%return) (match-info:matches? self))

Returns whether the previous match operation succeeded.

Parameters

match_info

a GMatchInfo structure

Passed as self

next?

(define-values (%return) (match-info:next? self))

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.

Parameters

match_info

a GMatchInfo structure

Passed as self

ref

(define-values (%return) (match-info:ref self))

Increases reference count of match_info by 1.

Parameters

match_info

a GMatchInfo

Passed as self

unref

(define-values () (match-info:unref self))

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.

Parameters

match_info

a GMatchInfo

Passed as self