Copyright	Copyright (C) 2007 John Goerzen
License	BSD3
Maintainer	John Lato <jwlato@gmail.com>
Stability	provisional
Portability	portable
Safe Haskell	Safe
Language	Haskell98

Data.ListLike.FoldableLL

Contents

FoldableLL Class
Utilities

Description

Generic tools for data structures that can be folded.

Written by John Goerzen, jgoerzen@complete.org

Synopsis

FoldableLL Class

class FoldableLL full item | full -> item where Source #

This is the primary class for structures that are to be considered foldable. A minimum complete definition provides foldl and foldr.

Instances of FoldableLL can be folded, and can be many and varied.

These functions are used heavily in Data.ListLike.

Minimal complete definition

foldl, foldr

Methods

foldl :: (a -> item -> a) -> a -> full -> a Source #

Left-associative fold

foldl' :: (a -> item -> a) -> a -> full -> a Source #

Strict version of foldl.

foldl1 :: (item -> item -> item) -> full -> item Source #

A variant of foldl with no base case. Requires at least 1 list element.

foldr :: (item -> b -> b) -> b -> full -> b Source #

Right-associative fold

foldr' :: (item -> b -> b) -> b -> full -> b Source #

Strict version of foldr

foldr1 :: (item -> item -> item) -> full -> item Source #

Like foldr, but with no starting value

Instances

FoldableLL CharStringLazy Char Source #
Methods foldl :: (a -> Char -> a) -> a -> CharStringLazy -> a Source # foldl' :: (a -> Char -> a) -> a -> CharStringLazy -> a Source # foldl1 :: (Char -> Char -> Char) -> CharStringLazy -> Char Source # foldr :: (Char -> b -> b) -> b -> CharStringLazy -> b Source # foldr' :: (Char -> b -> b) -> b -> CharStringLazy -> b Source # foldr1 :: (Char -> Char -> Char) -> CharStringLazy -> Char Source #
FoldableLL CharString Char Source #
Methods foldl :: (a -> Char -> a) -> a -> CharString -> a Source # foldl' :: (a -> Char -> a) -> a -> CharString -> a Source # foldl1 :: (Char -> Char -> Char) -> CharString -> Char Source # foldr :: (Char -> b -> b) -> b -> CharString -> b Source # foldr' :: (Char -> b -> b) -> b -> CharString -> b Source # foldr1 :: (Char -> Char -> Char) -> CharString -> Char Source #
FoldableLL Chars Char Source #
Methods foldl :: (a -> Char -> a) -> a -> Chars -> a Source # foldl' :: (a -> Char -> a) -> a -> Chars -> a Source # foldl1 :: (Char -> Char -> Char) -> Chars -> Char Source # foldr :: (Char -> b -> b) -> b -> Chars -> b Source # foldr' :: (Char -> b -> b) -> b -> Chars -> b Source # foldr1 :: (Char -> Char -> Char) -> Chars -> Char Source #
FoldableLL [a] a Source #
Methods foldl :: (a -> a -> a) -> a -> [a] -> a Source # foldl' :: (a -> a -> a) -> a -> [a] -> a Source # foldl1 :: (a -> a -> a) -> [a] -> a Source # foldr :: (a -> b -> b) -> b -> [a] -> b Source # foldr' :: (a -> b -> b) -> b -> [a] -> b Source # foldr1 :: (a -> a -> a) -> [a] -> a Source #

Utilities

fold :: (FoldableLL full item, Monoid item) => full -> item Source #

Combine the elements of a structure using a monoid. fold = foldMap id

foldMap :: (FoldableLL full item, Monoid m) => (item -> m) -> full -> m Source #

Map each element to a monoid, then combine the results

foldM :: (Monad m, FoldableLL full item) => (a -> item -> m a) -> a -> full -> m a Source #

Monadic version of left fold, similar to foldM.

sequence_ :: (Monad m, FoldableLL full (m item)) => full -> m () Source #

Evaluate each action, ignoring the results. Same as mapM_ id.

mapM_ :: (Monad m, FoldableLL full item) => (item -> m b) -> full -> m () Source #

A map in monad space, discarding results.