#!/usr/bin/env perl

use 5.010;
use strict;
use warnings;

my @test_strings = qw{""" "'" '"' ''' ""' "'' '"" ''"};

my $re = qr{ (?<FQ>"|') (??{ "[^$+{FQ}]+" }) \k<FQ> }x;

for (@test_strings) {
    say "Testing [$_] : ", (/$re/ ? '' : 'no '), 'match.';
}