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#!/usr/bin/perl

# Copyright 2013-2015, Paul Johnson (paul@pjcj.net)

# This software is free.  It is licensed under the same terms as Perl itself.

# The latest version of this software should be available from my homepage:
# http://www.pjcj.net

my $x = 1;
my $y = 1;

if ($x && !$y) {
    die "Urgh";
}

if ($x && $y) {
}

unless ($x && $y) {
    die "Urgh";
}

if (!($x && $y)) {
    die "Urgh";
}

# TODO - this does not get reported on correctly.  It is reported identically
# to the first case, but it should be the same as cases 2 - 4.
if (!$x || !$y) {
    die "Urgh";
}