MatchInfo

class MatchInfo(*args, **kwargs)

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

Methods

class MatchInfo

expand_references(string_to_expand: str) → str | None

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 replace().

The string_to_expand must be UTF-8 encoded even if RAW was passed to 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 None in which case string_to_expand must not contain references. For instance “foon” 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 check_replacement() to find out whether string_to_expand contains references.

Added in version 2.14.

Parameters:: string_to_expand – the string to expand

fetch(match_num: int) → str | None

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 match_all() or 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.

Added in version 2.14.

Parameters:: match_num – number of the sub expression

fetch_all() → list[str]

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 match_all() or 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.

Added in version 2.14.

fetch_named(name: str) → str | None

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.

Added in version 2.14.

Parameters:: name – name of the subexpression

fetch_named_pos(name: str) → tuple[bool, int, int]

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.

Added in version 2.14.

Parameters:: name – name of the subexpression

fetch_pos(match_num: int) → tuple[bool, int, int]

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 match_all() or 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.

Added in version 2.14.

Parameters:: match_num – number of the sub expression

free() → None: If match_info is not None, calls unref(); otherwise does nothing.

Added in version 2.14.

get_match_count() → int

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 match_all() or match_all_full(), the retrieved count is not that of the number of capturing parentheses but that of the number of matched substrings.

Added in version 2.14.

get_regex() → Regex: Returns Regex object used in match_info. It belongs to Glib and must not be freed. Use ref() if you need to keep it after you free match_info object.

Added in version 2.14.

get_string() → str: Returns the string searched with match_info. This is the string passed to match() or replace() so you may not free it before calling this function.

Added in version 2.14.

is_partial_match() → 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)dd$”. 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 PARTIAL_SOFT and PARTIAL_HARD flags. When they are used, the return code for match() or 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 is_partial_match().

The difference between PARTIAL_SOFT and PARTIAL_HARD is that when a partial match is encountered with PARTIAL_SOFT, matching continues to search for a possible complete match, while with PARTIAL_HARD matching stops at the partial match. When both PARTIAL_SOFT and 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.

Added in version 2.14.

matches() → bool: Returns whether the previous match operation succeeded.

Added in version 2.14.

next() → bool

Scans for the next match using the same parameters of the previous call to match_full() or 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.

Added in version 2.14.