[Haskell-beginners] Parametrizing [] as an instance of the Functor type class

[Alexander Berntsen]

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On 31/12/15 14:06, Olumide wrote:
> Overall, I'm a bit confused about the relationship between the type
>  constructor f and [].
f = []. In other words, [] *is* the type constructor.

In Haskell, [] is both the type constructor for lists *and* the term
level value for an empty list. This is unfortunate. In ghci you can
see this.

? :t []
[] :: [t] -- term level
? :k []
[] :: * -> * -- type level
- -- 
Alexander
alexander at plaimi.net
https://secure.plaimi.net/~alexander
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