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in reply to Re: tr///c doesn't seem to work as I expect
in thread tr///c doesn't seem to work as I expect

Wow.. maybe. Is that a valid range? I thought it meant '-' itself. That must be it.
  • Comment on Re^2: tr///c doesn't seem to work as I expect

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Re^3: tr///c doesn't seem to work as I expect
by james2vegas (Chaplain) on Sep 04, 2009 at 20:42 UTC
    From perlop:
    The character "-" is treated specially and therefore "\-" is treated +as a literal "-".


    The - indicates a range.

    if($data !~ /^[\ \-\~\007\012\015\035\036\037]*$/) { $data =~ tr/[\ \-\~\007\012\015\035\036\037]/ /cs; }
    is probably what you need.

      One small point:

      In the  tr operator, the  [ and  ] characters have no special meaning. (In a 'normal' regex, they define a character set.) In the expressison (as taken from the OP)
          $data =~ tr/[\ -\~\007\012\015\035\036\037]/ /cs;
      the  [ and  ] characters simply represent themselves. This has no effect in this particular case, however, since these characters are also included in the range  \ -\~ that includes, IIRC, all printable ASCII characters. (I think a space qualifies as a 'printable' character.)

      Thanks. Given the rest of the code (not shown), actually the range makes a lot more sense. It might not be 'correct', but I at least understand what's going on now. :)