Well, since everyone is posting their permutors, here's mine: 
sub permute {
  my $last = pop @_;
  unless (@_) {
    return @$last;
  }
  return map { my $left = $_; map "$left$_", @$last } permute(@_);
}

[download]

-- Randal L. Schwartz, Perl hacker

In reply to My permutor by merlyn
in thread How can I improve this? by Dogg

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