transformers-0.5.4.0: Concrete functor and monad transformers

Description

Selection monad transformer, modelling search algorithms.

Synopsis

type Select r = SelectT r Identity Source #

select :: ((a -> r) -> a) -> Select r a Source #

Constructor for computations in the selection monad.

runSelect :: Select r a -> (a -> r) -> a Source #

Runs a Select computation with a function for evaluating answers to select a particular answer. (The inverse of select.)

newtype SelectT r m a Source #

SelectT is not a functor on the category of monads, and many operations cannot be lifted through it.

Constructors

 SelectT ((a -> m r) -> m a)

Instances

Runs a SelectT computation with a function for evaluating answers to select a particular answer. (The inverse of select.)