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Re: getting 0 to print

by Arien (Pilgrim)
on Jan 13, 2003 at 23:21 UTC ( #226646=note: print w/replies, xml ) Need Help??

in reply to getting 0 to print

In addition to other changes, you may want to write trim like this:

sub trim { my @out = wantarray ? @_ : shift; return "" unless @out; for (@out) { $_ = "" => next unless defined; tr/|\n\r//d; s/^\s+|\s+$//g; } return @out; }

— Arien

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Re: Re: getting 0 to print
by rbc (Curate) on Jan 13, 2003 at 23:32 UTC
    Oooh! that work too! thanks!

    I have never seen this ...
    $_ = "" => next unless defined;
    ... before. Could you explain how that works.
    It would be most enlightening.

      I have never seen this ...

      $_ = "" => next unless defined;

      ... before. Could you explain how that works.

      I'm not sure what part puzzles you, so...

      • defined implicitly refers to $_.
      • unless (...) { ... } can be written as ... unless ... if the block is just a simple statement.
      • ... => ... is another way to write ... , ... (apart from the fact that => will autoquote any word left of it).
      • In scalar context (ie the way used here) the comma (in either notation) evaluates its both arguments from left to right (and returns the value value of the last argument evaluated).

      (You can find all details in perlsyn and perlop.)

      In other words, that line is just one of the many variations of writing:

      unless (defined $_) { $_ = ""; next }

      — Arien

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[SuicideJunkie]: So, possibly interesting thing; I had that script which was using more than all the ram to open an absurdly large spreadsheet. I set it up to spin overnight nightly, so it stopped releasing memory since it was never fully exited.
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