in reply to Re: Re:^2 Golf: string complement
in thread Golf: string complement

But, when you print, it forces scalar context. The output of the print statement is the same. Same if you assigned result of sub to a scalar explicitly: 
my $result = invert($string);

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is the same with or without the join.

.02

cLive ;-) - see above

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Re: Re: Re: Re:^2 Golf: string complement
by BrowserUk (Patriarch) on May 16, 2004 at 01:23 UTC

    Not quite. A list grep in a scalar context return the size of the list.

    sub invert {
    #23456789012345678901234567890
    grep/[^\Q@_\E]/,map{chr}1..255
};

$inverted = invert( 'Just Another Perl Hacker!' );

print $inverted;
237

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    237 + 18 (unique characters in the string) = 255.

    Examine what is said, not who speaks.
    "Efficiency is intelligent laziness." -David Dunham
    "Think for yourself!" - Abigail
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[d/l]
      I actually already did toy with the idea of interpolating the output of grep into a string, but it turned out to fail to gain any ground; it works, but it's no shorter, plus to get identical output you would have to also set $" to '' (empty string), which takes additional keystrokes..

      My 37 keystroke method: 

      sub invert {
    #234567890123456789012345678901234567
    join'',grep/[^\Q@_\E]/,map{chr}1..255
}

      [download]

      And now without join, but with double-quotish interpolation: 

      sub invert {
    #234567890123456789012345678901234567
    "@{[grep/[^\Q@_\E]/,map{chr}1..255]}"
}

      [download]

      Dave

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Re: Re: Re: Re:^2 Golf: string complement
by japhy (Canon) on May 16, 2004 at 01:23 UTC
    Huh? grep() in scalar context returns a number, not a join()ed list of elements that passed through. And print() doesn't "force scalar context" -- in fact, it invokes list context, which is the only reason why print invert($string) works.
    _____________________________________________________
    Jeff[japhy]Pinyan: Perl, regex, and perl hacker, who'd like a job (NYC-area)
    s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;
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