capture

extracts groups matched by a regular expression pattern

(string subject, string pattern) -> list

Matches a regular expression pattern against a given subject string.

If pattern does not match given subject in its entirety, returns an empty list.

If pattern matches given subject in its entirety, a list of strings matched by capturing groups is returned.

Index 0 contains the entire input string, and subsequent indexes contain matched groups. Group indexes correspond to the sequence of opening group parentheses of capturing groups in the pattern.

If a group is optional, and is not matched by the input string, its value in the list is nil.

If a capturing group is inside a quantifier, only the last matched string is captured.

Returns nil if any argument is nil.

Parameters