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

[download]

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

In reply to Re: Re: Re: Re:^2 Golf: string complement by BrowserUk
in thread Golf: string complement by japhy

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