cpp/regex/match results

The class template holds a collection of character sequences that represent the result of a regular expression match.

This is a specialized allocator-aware container. It can only be default created, obtained from std, or modified by std or std. Because holds stdes, each of which is a pair of iterators into the original character sequence that was matched, it's undefined behavior to examine  if the original character sequence was destroyed or iterators to it were invalidated for other reasons.

The first std (index 0) contained in a always represents the full match within a target sequence made by a regex, and subsequent stdes represent sub-expression matches corresponding in sequence to the left parenthesis delimiting the sub-expression in the regex.

meets the requirements of a and of a, except that only copy assignment, move assignment, and operations defined for a constant containers are supported, and that the semantics of comparison functions are different from those required for a container.

Specializations
Several specializations for common character sequence types are provided: