On Thu, Sep 10, 2009 at 14:43, Peter Verswyvelen wrote:

On Thu, Sep 10, 2009 at 11:47 AM, Roman Cheplyaka wrote:
> step x g a = g (f a x)
>
> is, thanks to currying, another way to write
>
> step x g = \a -> g (f a x)

I thought currying just meant

curry f x y = f (x,y)

Isn't the reason that

f x y z = body

is the same as

f = \x -> \y -> \z -> body

just cause the former is syntactic sugar of the latter?

In some functional programming languages, these are not equivalent. For example, Clean does not have currying, so

f :: Int Int -> Int
f x y = x + y

is not the same as

f :: Int -> Int -> Int
f x = (+) x

Notice the difference in types. The first is more like 'f :: (Int, Int) -> Int' in Haskell.

Sean