Re: Golf: Arbitrary Alphabetical Sorting

[merlyn]

Well, here's a cut at it, even though it's not golfed yet:

sub o {
  my ($a, $w) = @_;
  my %m; @m{@$a} = (a..z);
  my $k = join "", keys %m;
  my $v = join "", values %m;
  map { eval "tr/$v/$k/"; $_ } sort map { eval "tr/$k/$v/"; $_ } @$w;
}

-- Randal L. Schwartz, Perl hacker

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update: and of course, it's doggy slow. That eval needs to be saved, like in a coderef or something.

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update2: Bleh. RIght. 'a'..'z' was being presumptive that "letter" meant "letter" like I knew it. Here's the patch to make it work for larger sets, for reasonable values of work:

sub o {
  my ($a, $w) = @_;
  my %m; @m{@$a} = 1..@$a;
  my $k = join "", map {sprintf "\\%03o", ord $_} keys %m;
  my $v = join "", map {sprintf "\\%03o", $_ } values %m;
  map { eval "tr/$v/$k/"; $_ } sort map { eval "tr/$k/$v/"; $_ } @$w;
}