monoid-subclasses-0.4.0.1: Subclasses of Monoid

Safe HaskellSafe-Inferred
LanguageHaskell2010

Data.Monoid.Instances.Concat

Description

This module defines the monoid transformer data type Concat.

Synopsis

Documentation

data Concat a Source

Concat a is a newtype wrapper around Seq a. The behaviour of the Concat a instances of monoid subclasses is identical to the behaviour of their a instances, up to the pure isomorphism.

The only purpose of Concat then is to change the performance characteristics of various operations. Most importantly, injecting a monoid into a Concat has the effect of making mappend a constant-time operation.