const -base +transformers

Constant :: a -> Constant a b
transformers Data.Functor.Constant
newtype Constant a b
transformers Data.Functor.Constant
Constant functor.
module Data.Functor.Constant
transformers Data.Functor.Constant
The constant functor.
getConstant :: Constant a b -> a
transformers Data.Functor.Constant