Module Data.Functor.Const

This simple module defines the const functor known from Haskell's base libraries. It defines a wrapper around a constant value that "ignores" functions mapped over it.

Summary of exported operations:

Exported datatypes:

newtype Const

The Const functor which returns a constant for any fmap, i.e., a wrapper around a constant value that ignores functions mapped over it.

Example: 

> fmap (++ "world") (Const "Hello")
Const "Hello"

Constructor:

  • Const :: a -> Const a b

    Fields:

    • getConst :: a

Exported operations: