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pdcawley,
Eager to try my tail recursion, I tried your example and was bummed when it didn't work. I figured out that to make it work you had to do something like:
print tail_factorial(1, 8);
Where you had to supply an initial total for it to work. Here is a slightly modified version.
sub tail_factorial { my ($n, $total) = @_; $total = 1 if ! $total; return $total if ! $n; @_ = ($n - 1, $total * $n); goto &tail_factorial; }
To verify that it works I tested it for a value of 150 - no deep recursion errors - yeah. Thanks for the p6 weekly summaries too.

Cheers - L~R


In reply to Re: Pure Perl tail call optimization by Limbic~Region
in thread Pure Perl tail call optimization by pdcawley

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