[Haskell-cafe] Re: Shouldn't this loop indefinitely => take (last [0..]) [0..]

Felipe Lessa felipe.lessa at gmail.com
Sun Apr 6 10:30:20 EDT 2008


On Sun, Apr 6, 2008 at 11:12 AM, John Meacham <john at repetae.net> wrote:
>  I implemented this efficient lazy natural class once upon a time. it
>  even has things like lazy multiplication:
[...]
>  instance Num Nat where
>     Zero + y = y
>     Sum x n1 + y = Sum x (y + n1)
>     --x + Zero = x
>     --Sum x n1 + Sum y n2 = Sum (x + y) (n1 + n2)
[...]

May I ask you why the last line above was commented out?

Thanks!

-- 
Felipe.


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