A more succinct (but semantically equivalent) version of: 
foreach (@myarray) {
      $myhash{$_} = 1;
}

[download]
is 
$myhash{$_}++ for @myarray;

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I once heard (somewhere) that doing 
if ($myhash{'blah'}) {
    do_something();
}

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(i.e. refering to a key in a hash) causes that key to come into existence, so the above expression may always evaluate as true. I haven't been able to prove this, but I think what you want is the exists function: 
if (exists($myhash{'blah'})) { 
  # Do something here
}

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I quite like using 'exists', it makes code far more readable.

In reply to RE: Re: in function? by SuperCruncher
in thread in function? by Anonymous Monk

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