On 06/03/2010 10:14 AM, Gabriel Riba wrote:
No need for runtime errors or exception control
hd :: List!Cons a -> a
hd (Cons x _) = x
This is already doable using GADTs:
data Z
data S n
data List a n where
Nil :: List a Z
Cons :: a -> List a n -> List a (S n)
hd :: List a (S n) -> a
hd (Cons x _) = x
tl :: List a (S n) -> List a n
tl (Cons _ xs) = xs
- Jake
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