None of the code shown so far matches the original. When you shift off @_, it actually removes the value, allowing you to use the rest of @_ at your leisure. 
#!/usr/bin/perl

use warnings;
use strict;

sub function1 {
    my $var = defined $_[0] ? shift : 'No argument';
    print "$var\n";
}

function1('zero');
function1(0);
function1('0');
function1(0e0);
function1('foolio');
function1();

[download]

In reply to Re: How to assign string "0" in short circuit by saberworks
in thread How to assign string "0" in short circuit by nikhil.patil

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