That's certainly true. I often use that, and have no idea why I didn't suggest it myself!

Generally speaking the reason to use this idiom is when you need to loop through a list and in each iteration you need to take one or more items from the list.This kind of thing:

use strict;
use warnings;
use Data::Dumper;

my @input = (
    'foo:'   => 1,
    'bar:'   => 2,
    'baz',  # no colon, so value is "1"
    'quux:'  => 3,
);

my %output;
while (@input)
{
    my $key = shift @input;
    
    if ($key =~ /\A(.+):\z/)
    {
        $output{$1} = shift @input;
    }
    else
    {
        $output{$key} = 1;
    }
}

print Dumper \%output;

[download]

If you only need to step through the list one at a time, use foreach; it's clearer.

use Moops; class Cow :rw { has name => (default => 'Ermintrude') }; say Cow->new->name

In reply to Re^3: Different result for 'foreach' vs 'while shift' arrayref by tobyink
in thread Different result for 'foreach' vs 'while shift' arrayref by gvandeweyer

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