I KNEW I'd read something about this before. p383 in Programming Perl, 3rd ed.

By calling keys in a scalar context, we reset its internal state to ensure that the next each used in the return statement will get the first key. 

sub find_stuff {
   my $self = shift;

   scalar keys %$self;
   while (my $k = each %$self) {
       return $k if ($self->{$k}->{blablah});
   }

   return undef;
}

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Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.

I shouldn't have to say this, but any code, unless otherwise stated, is untested

In reply to Re: Optimization, side-effects and wrong code by dragonchild
in thread Optimization, side-effects and wrong code by cbraga

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