Not hard obviously ;-) However, I do miss the ability to say succinctly whether two things are the same "object" or not - something like Common Lisp's eq, Pop-11's == or python's is.

I admit Perl's eq works for this case 99% of the time, I don't like using it for identity checks because:

• It's not explicit enough. I want to say "these two things are the same" not "these two things expressed as strings are the same"
• Stringification has got to be more expensive than a direct comparison internally.
• It can fail when you have overloading of eq or "". I don't like writing code that can fail, even if it is only a few edge cases :-)

It's easy to write your own obviously - this does the job:

#! /usr/bin/perl

use strict;
use warnings;
use Scalar::Util qw(refaddr);

sub same {
    ref($_[0]) && ref($_[1]) && refaddr($_[0]) == refaddr($_[1])
    || refaddr(\$_[0]) == refaddr(\$_[1]);
};

use Test::More 'no_plan';
our ($x, $y, $z) = (1,1);
*z = *x;

ok  same($x, $x),   'x is x';
ok  same(\$x, \$x), 'ref x is ref x';
ok !same($x, $y),   'x not y';
ok  same($x, $z),   'x is z';
[download]

But, in my opinion, something this basic should be in the base language... but I guess that's what perl6 is for :-)

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