#!/usr/bin/perl -w
use strict;

sub matches_regex{
## Purpose:  Means to test wether a Regular Expression 
##           matches what you think it matches.
## Requires: One regex and one a scalar to use it on.
## Returns:  True (1) for matches, false (0) for non-matches.
## ==========================================================
## Usage: "matches_regex( 'string to test', 'regex to use' );
## ==========================================================

	my ($string, $regex) = @_;
	return( $string =~ /$regex/ );
}


# ===== illustrations =====
my $string  = '4245581234567890';
my @regexes = ('^[424558][0-9]{10,10}$'
              ,'^(424558)[0-9]{10,10}$'
              ,'^424558[0-9]{10,10}$'
              );

foreach my $regex( @regexes ){
	print "Testing string '$string' for regex '$regex'\n";
	if( matches_regex( $string, $regex ) ){
		print "\tMatched\n";
	} else {
		print "\tDid not match\n";
	}
}