Data.Delta

Delta types are instances of the type class Delta. An instance Delta delta indicates that the type delta is a delta type of the corresponding base type Base delta. The apply function applies a delta to the base type.

Delta types can be transformed into each other using the Embedding type. Embeddings can be composed using the Semigroupoid class.

Examples:

apply (Replace 7) 3 = 7

apply [Append [1], Append [2]] [3] = [1,2,3]

apply [Insert 'c', Delete 'b'] (Set.fromList "ab") = Set.fromList "ac"

∀(x :: Set Char). apply [Delete 'b', Insert 'b'] x = apply (Delete 'b') x

Modules

The present module re-exports the following child modules for convenience.

Core definitions: Delta class, apply function, Base type family.

Core instances: Replace, Endo, Maybe, '[]'.

module Data.Delta.Core

Delta types for common containers.

module Data.Delta.List

module Data.Delta.Set

Embeddings of delta types and helper functions.

module Data.Delta.Embedding

Re-export Data.Semigroupoid for convenience.

module Data.Semigroupoid