#!/usr/bin/perl
use strict;
use warnings;

my @tests = ("\% only 1 profile is allowed\n\n",  # Should fail
             "\n\n",                              # Should pass
             "",                                  # Should pass
             );

my $regex = "(?!.*\\S)";
for (@tests) {
    print $_ =~ qr{$regex}ms ? "$_\n REGEX MATCHED\n" : "$_\n FAILED!\n";
}