Personally, I try to parameter validation at the beginning of the sub, and return validation at the end of the sub (provided its not going to cause a performance problem by needing to execute large amounts of unnecessary code). 
sub sg {
my $result;

  die "COND isn't valid" if (COND eq undef);

  if (COND) {
    $result = 1;
  } else {
    $result = 2;
  };

  die "result isn't valid" if ($result eq undef);

  return $result;
}

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In reply to Re: if else and not reachable coding style by Anonymous Monk
in thread if else and not reachable coding style by szabgab

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