#! /usr/bin/perl
use Test::More tests => 1;

use Test::LectroTest::Compat;
use Test::Differences;

sub square {
    my $square = $_[ 0 ] * $_[ 0 ];
    return [ $square, $square ];
}

my $square_property = Property {
  ##[ x <- Int #]##
    my $sq = $x * $x;

    eq_or_diff( square( $x ), [ $sq, $sq ] );
}, name => "Finding \$x's square. Twice!";

holds( $square_property );

##</code><code>##

shiny:~/dev/perl$ perl lec.pl 
1..1
ok 1 - property 'Finding $x's square. Twice!' (1000 attempts)