FoldA is:module

Class of data structures that can be folded to a summary value.

A class of non-empty data structures that can be folded to a summary value.

Foldable functions, with wrappers like the Safe module.

Re-exports a subset of the Data.Foldable1 module along with some additional combinators that require Foldable1 constraints.

Contains utility functions for working with tuples.

Foldable1 is a typeclass like Foldable but for non-empty structures. For example, NonEmpty, Identity. Foldable1 has all type-safe and total methods like head1, maximum1 in contradiction with Foldable.

This module provides Foldable and Traversable related types and functions.

Generic tools for data structures that can be folded. Written by John Goerzen, jgoerzen@complete.org

Foldable types. A minimal implementation of this interface is given by either FoldMap or Foldr, but a default still needs to be given explicitly for the other.

data MyType a = ... {- Some custom Foldable type -}

-- Method 1: Implement Foldr, default FoldMap.
type instance Eval (Foldr f y xs) = ... {- Explicit implementation -}
type instance Eval (FoldMap f xs) = FoldMapDefault_ f xs {- Default -}

-- Method 2: Implement FoldMap, default Foldr.
type instance Eval (FoldMap f xs) = ... {- Explicit implementation -}
type instance Eval (Foldr f y xs) = FoldrDefault_ f y xs {- Default -}

Class of data structures that can be folded to a summary value.

Efficient enumeration of subsets of triangular elements. Given a list [1..n] we want to enumerate a subset [(i,j)] of ordered pairs in such a way that we only have to hold the elements necessary for this subset in memory.

This shows how Foldable is basically Recursive specialized to lists. The true operation of Foldable is toList. As these few operations have the usual signatures, the rest of the type class can be implemented in the as in base.

Overrides for problematic Foldable functions.

A module to provide the extended variants to convert a InsertLeft instance structure with some values to another one with the values from the pre-defined structure. Similar to the measurement of the quantum state observables with the discrete spectrum. For performance reasons it is better to use module ListQuantizer whenever possible (especially if the given Foldable and InsertLeft instances are just lists). Contrary to TwoQuantizer module, the results in every function here depend not just on the two values, which the point is located in between, but on the whole structure. Defined for just positive real numbers of Double type.