<INTERFACE> The <CD/RegExpFn/ functor <SEEALSO> <SIGREF/REGEXP/ <SIGREF/REGEXP_PARSER/ <SIGREF/REGEXP_ENGINE/ </SEEALSO> <PP> This functor creates a concrete regular expressions matcher by glueing together a concrete syntax and a matching engine.<PP> <SIGBODY> <SPEC> <SUBSTRUCT>P<ID>REGEXP_PARSER</SUBSTRUCT> <COMMENT> <PP> This is the structure implementing the frontend (syntax) of regular expressions. <SPEC> <SUBSTRUCT>E<ID>REGEXP_ENGINE</SUBSTRUCT> <COMMENT> <PP> This is the structure implementing the backend (engine) of regular expressions. </SIGBODY> <ID>REGEXP </INTERFACE>