The following simple subroutine: 
sub log_msg {
  my $log_msg = shift;
  print "value $script::debug";
  if ($script::debug) {
      print sprintf "(%s) $log_msg \n", shell_date;
  }
}

[download]
still prints log messages when the printed value of $script::debug is 0.

So this yields two questions, and I would like an answer to both:

  • What are all the false values in Perl? I know of the following:
    1. "0"
    2. ""
    3. 0
    4. 0.0
  • How do one brute-force print every character in a string even if it is typically unprintable? That is, my guess is that things are being printed even when $script::debug appears to be zero when in fact there may be some hidden control char or something in the string.

    In reply to What are all the false values in Perl ((conditional, boolean, whitespace, unprintable characters) by princepawn

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