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in reply to Re: Re (tilly) 1: Golf: Arbitrary Alphabetical Sorting
in thread Golf: Arbitrary Alphabetical Sorting

First of all that doesn't work because shift returns a reference. You need it to dereference the first element into an array. Secondly you know I love a challenge..like 76 characters: 
sub o{
($c,$s,$")=@_;sub t{$_=pop;s/./~0+index"@$c",$&/ges;$_}sort{t($a)cmp t
+$b}@$s
}

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(I have to waste 3 on removing spaces, dang.)

UPDATE
In 5.6.x it appears you need to spend another character: 

sub o{
($c,$s,$")=@_;sub t{$_=pop;s/./1e9+index"@$c",$&/ges;$_}sort{t($a)cmp 
+t$b}@$s
}

[download]

UPDATE 2
Saving another character..back to 76. 

sub o{
($c,$s,$")=@_;sub t{s/./1e9+index"@$c",$&/ges;$_}sort{t($_=$a)cmp t$_=
+$b}@$s
}

[download]

UPDATE 3
Throwing in tadman's improvement, 75: 

sub o{
($c,*w,$")=@_;sub t{s/./1e9+index"@$c",$&/ges;$_}sort{t($_=$a)cmp t$_=
+$b}@w
}

[download]
(Note that chr returning 2 chars wouldn't make Unicode come out right. Hence I am keeping the 1e9 trick.)

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Re: Re (tilly) 3: Golf: Arbitrary Alphabetical Sorting
by tadman (Prior) on May 10, 2001 at 01:39 UTC
    You can save a single character by using a glob, such as: 
    sub o {
($l,*w,$")=@_;sub g{$_=pop;s/./chr index"@$l",$&/ges;$_}sort{g($a)cmp 
+g+$b}@w
}

    [download]
    So *w ... @w instead of $w ... @$w.

    '1e9' or 'chr' vary only in that '1e9' would support an alphabet of length > 255, but if you're using UNICODE, then chr would likely return two characters anyway.
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Re^4: Golf: Arbitrary Alphabetical Sorting
by tadman (Prior) on May 10, 2001 at 03:04 UTC
    TMTOWTDI, as they say, and this one appears to be 70 characters: 
    sub o {
($c,*w,$")=@_;sub t{eval"y/@$c/\0-\377/";$_}sort{t($_=$a)cmp t$_=$b}@w
}

    [download]
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[d/l]
      Unfortunately, that fails if @$c includes a slash. Fixing this bumps it up to 74 characters: 
      sub o {
    ($c,*w,$")=@_;sub t{eval"y/\Q@$c\E/\0-\377/";$_}sort{t($_=$a)cmp t
+$_=$b}@w
}

      [download]
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[d/l]
        I find this turn of events absolutely astounding, and I only have one thing to add.

        It may not display well, but the two escape sequences can be replaced by the actual characters. This brings it back down to 70. Here is the paste from my system, this may not work on yours: 

        sub o{
($c,*w,$")=@_;sub t{eval"y/\Q@$c\E/-ÿ/";$_}sort{t($_=$a)cmp t$_=$b}@w
}

        [download]

        UPDATE
        It definitely won't work on yours. It seems the \0 was trimmed from the output. To get what you need go back to chipmunk's post, download his code to a file, then run this: 

        perl -pi.bak -e 's/\\(\d+)/chr(oct($1))/e' filename

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        (Use " instead of ' on Windows.) The resulting file will have the key subroutine reduced to 70 characters, and will still run.
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