unbound-generics-0.4.2: Support for programming with names and binders using GHC Generics
Copyright(c) 2014 Aleksey Kliger
LicenseBSD3 (See LICENSE)
MaintainerAleksey Kliger
Stabilityexperimental
Safe HaskellSafe-Inferred
LanguageHaskell2010

Unbound.Generics.LocallyNameless.Internal.Fold

Description

Some utilities for working with Folds.

If you are using lens, you don't need this module.

Documentation

type Fold s a = forall f. (Contravariant f, Applicative f) => (a -> f a) -> s -> f s Source #

type Traversal' s a = forall f. Applicative f => (a -> f a) -> s -> f s Source #

toListOf :: Fold s a -> s -> [a] Source #

filtered :: (a -> Bool) -> Traversal' a a Source #

justFiltered :: (a -> Maybe b) -> Fold a b Source #

foldMapOf :: Getting r s a -> (a -> r) -> s -> r Source #