Now one problem of course is that perl does not do this type of optimization :)
Sure, but you can tell it to do that. :-) 
sub factorial {
    my ($n, $accumulator) = @_;
    $accumulator ||= 1;
    if ($n == 0) { 
         return $accumulator;
    }
    @_ = ($n - 1, $n * $accumulator);
    goto &factorial;
}

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In reply to Re^5: Behold! The power of recursion. by audreyt
in thread Behold! The power of recursion. by DigitalKitty

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