cpp/regex/match results/ready

Indicates if the match results are ready (valid) or not.

A default-constructed match result has no result state (is not ready), and can only be made ready by one of the regex algorithms. The ready state implies that all match results have been fully established.

The result of calling most member functions of the match_results object that is not ready is undefined.

Return value
if the match results are ready, otherwise.