Match events are created with the match and regex
commands. A match event occurs when the pattern specified in
the match or regex command has been matched in
the input. Characters are only input during the execution of
wait commands. In order for a pattern to match, the
first matching character of the pattern must be read
after the event is created (i.e., during a subsequent
wait command).
When the pattern is matched, chat script execution continues starting at the target label. When multiple patterns match on the same input character, mpd chooses the first one defined to be the one that matches.
The pattern is either plain text or an extended regular expression (see below).