As for pattern-matching, the absolute coolest demonstration of this is quicksort in 2 or 3 lines of Haskell

Just for the fun of it, and for comparision, here is what (I think) the equivalent perl would be (for numeric sorts, I don't know if Haskell has a separate character comparision operator like Perl):

sub qs {
  return unless @_;
  my $x = shift;
  return qs(grep($_ < $x, @_)), $x, qs(grep($_ >= $x, @_));
}

[download]
It can be done without the $x temp variable and the shift (saving one line), but then it's less readable IMO.

In reply to Re^2: RFC: A Perlesque Introduction to Haskell, Part One (draft) by runrig
in thread RFC: A Perlesque Introduction to Haskell, Part One (DRAFT) by FoxtrotUniform

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