If I understand correctly, ¬ is the logical not. It's a function from booleans to booleans (denoted by it's type: Bool -> Bool) because it takes as its argument a boolean to negate and returns the negation of its parameter. Hoping to have helped you, Loic

On Wed, 29 Jun 2011 14:55:50 +0000, Roelof Wobben wrote: Hello,

I'm now following the book Programming in Haskel by Hutton. IM now reading the chapter about types.

But I don't understand this :

False :: Bool True :: Bool ¬  :: Bool  ---> Bool

So False  and True has the type Bool. That's clear.

I find out that ¬ makes the opposite of True and False. But why is it also the type Bool --> Bool