in reply to Apocalypse 4 on perl.com

I thought the switch statement was completely cool until I saw default. Ick. I'd like this much better: 

given EXPR {
      when EXPR { ... }
      when EXPR { ... }
      ...
      otherwise { ... }
}

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My 0.02$US.

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Re: Re: Apocalypse 4 on perl.com
by adamsj (Hermit) on Jan 19, 2002 at 07:10 UTC
    I know what you mean, but given (sigh) how often this'll be used, I think it's better to Huffman it. If anyone has a brilliant idea for a shorter keyword than default, I hope they'll send it in.

    adamsj

    They laughed at Joan of Arc, but she went right ahead and built it. --Gracie Allen

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      How about nothing? 
      given ($foo) {
  when (1) {print "One";};
  when (2) {print "Two";};
  print "Didn't fit any case we know about";
}

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      Indent to taste.

      UPDATE
      I don't think that "normal code" will often see a difference. While I can dream up situations where I think it matters, in all of them you are doing evil, awful things that you probably shouldn't. (Like using a default to shortcircuit out of a function.)

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        That is already defined to work but doesn't solve the problem of the presense of a real "default" block changing the handling of exceptions.

                - tye (but my friends call me "Tye")
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      If anyone has a brilliant idea for a shorter keyword than default, I hope they'll send it in.
      Not shorter, but I think it's easier to read and a lot better: 
      given $foo {
 when 1 { ... }
 when 2 { ... }
 when we have tried all other options and
      really have nothing left but this last resort { ... }
}

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      :) 

      2;0 juerd@ouranos:~$ perl -e'undef christmas'
Segmentation fault
2;139 juerd@ouranos:~$

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      I pondered that for a bit but the best I could to was orelse. But that's even worse. :(.

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Re^2: Apocalypse 4 on perl.com
by Aristotle (Chancellor) on Jan 20, 2002 at 13:43 UTC
    By Larry's explanation, the idea of default was to prevent given's which don't have any when's from looking funny.
    Makeshifts last the longest.
[reply]

      Hmmm ... 

      given EXPR {
      otherwise { ... }
}

given EXPR {
      default { ... }
}

      [download]

      default definitely looks better here. I wonder how often people write empty switch statements though? Then again, given isn't your father's switch so past coding patterns may very well not apply.

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Perl 6 - A Better Switch-Case Default?
by metadoktor (Hermit) on Jan 26, 2002 at 16:54 UTC
    Hmmm...how about... 
    given EXPR 
{
     when EXPR { }
     when EXPR { }
     ...
     japh {      }
}

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    ha, ha...

    metadoktor

    "The doktor is in."

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      You are missing a colon. 
      given EXPR 
{
     when EXPR { }
     when EXPR { }
     ...
     japh: {      }
}

      [download]
      Happy to help,
      Ben

      :-)

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