"shift could easily return an empty list and $x is still undef."

It could easily, yes. But it doesn't. And it's documented as retuning undef. To do something different may well subtly break a lot of code on CPAN.

That said, shift is one of those keywords that Perl allows you to override...

use subs 'shift';

sub shift (+) {
  my $arr = $_[0];
  @$arr ? CORE::shift(@$arr) : ();
}

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

In reply to Re^3: shift in list context buggy? by tobyink
in thread shift in list context buggy? by LanX

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