use Perl

I just had an epiphany about how to make the AI::Prolog parser work much better. It would be cleaner and faster and probably allow for proper operators. The latter would allow me to do this:

X is Y + Z * 2.

Instead of:

is(X, plus(Y, mult(Z, 2))).

The latter, of course, is just plain ugly. I've also figured out a better way to handle precedence which might allow me to change the Prolog syntax at runtime (op/3 allows this in normal Prolog).

The only problem with my new idea is that I don't have time :(

In other news, Randal found a nifty solution to a weird problem. Someone wanted to count all instances of a string in another string, even if they were overlapping. So 'AA' can be found in 'AAAA' 3 times. Randal's solution, though Perl, is straight from Prolog:

sub match_count {
  my ($string, $pattern) = @_;
  my $n = 0;
  $string =~ /$pattern(?{ $n++ })(?!)/;
  return $n;
}

Neat, eh?