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ironcamel/recursive-closure.pl

Created March 25, 2012 18:43
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Recursive closure
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recursive-closure.pl
my $factorial = sub {
my $val = shift;
return $val * __SUB__->($val - 1) if $val > 1;
return $val;
};
print $factorial->(5);
@oylenshpeegul
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The spankin' new Functional::Utility module has a y_combinator routine!

use Functional::Utility qw(y_combinator);

my $factorial = y_combinator {
    my $val = shift;

    return sub {
        my $n = shift;
        return $n if $n == 1;
        return $n * $val->($n - 1);
    };
};

say $factorial->(5);

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