The shift operator returns an undefined value if the array has no more elements. : Special Variables « Language Basics « Perl

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Perl » Language Basics » Special Variables

The shift operator returns an undefined value if the array has no more elements.


   



#!/usr/bin/perl -w



# Get first argument.

$arg = shift(@ARGV);



# Loop while there is an argument.

while (defined $arg) {

    print "$arg\n";

    

    # Get next argument.

    $arg = shift(@ARGV);

}

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