I know variants of the following bug have been discussed in the Monastery recently, but I didn't find this particular one. My apologies in advance if I missed it.

Spot the bug:

sub foo {
  my $hashref = shift;
  while ( my ( $key, $value ) = each %$hashref ) {
    return if sometest( $key );
    frobnicate( $key, $value );
  }
}

[download]

BTW, there's nothing arcane about this bug. It's vanilla Perl, but it's easy to miss.

<Reveal this spoiler or all in this thread>

Update: The original title of this thread ("Buglet") was confusing, so, by popular demand, I changed it. I hope the new title is an improvement.

the lowliest monk

In reply to Spot the bug by tlm

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