[Haskell-cafe] Function Types

Tim Chevalier catamorphism at gmail.com
Mon Oct 22 22:45:51 EDT 2007


On 10/22/07, PR Stanley <prstanley at ntlworld.com> wrote:
> f x = x
> x :: a
> f x :: b
> therefore f :: a -> b
> x = a and x = b
> therefore a = b
> therefore f :: a -> a
> Simple mappings are easy to work out. It's the more detailed stuff
> I'm not sure about.
> f g x y = g x (y x)
>

Benjamin Pierce's _Types and Programming Languages_ has some good
chapters on type inference.

Cheers,
Tim

-- 
Tim Chevalier * catamorphism.org * Often in error, never in doubt
"Ever wonder why 'bus error core dump' is the standard C program crap
out?  Because C freely hands out random pointers to anyone that asks.
Slut."  -- Olin Shivers


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