#!/usr/bin/perl use strict; use warnings; use 5.014; use Parse::RecDescent; # $::RD_TRACE = 1; my $text = <<'CONTENT'; Y 034309201607258 1 Q 02751VACANT / CLOSE G .... ... ... T RCRC 0810010 T RDRD 0810010 A 22OP A 13O A 12O P 3472CHSK00010014 Z 034309201607258 CONTENT my $parser1 = Parse::RecDescent->new(<<'GRAMMAR'); startrule : HeadRule OtherRule(s) TrailerRule HeadRule : /^Y.+$/m TrailerRule: /^Z.+$/m OtherRule: /^(?![YZ]).*$/m GRAMMAR print "Valid data\n" if defined($parser1->startrule($text));