Control.Instances.Morph

Documentation

class GenMorph db m1 m2 where

A generalized version of Morph. Can work on different rulesets, so this should be used if the ruleset is to be extended.

Minimal complete definition

genMorph

Methods

genMorph :: db -> m1 a -> m2 a

Lifts the first monad into the second.

class Morph m1 m2 where

States that m1 can be represented with m2. That is because m2 contains more infromation than m1.

The MMorph relation defines a natural transformation from m1 to m2 that keeps the following laws:

morph (return x)  =  return x
morph (m >>= f)   =  morph m >>= morph . f

It is a reflexive and transitive relation.

Minimal complete definition

morph

Methods

morph :: m1 a -> m2 a

Lifts the first monad into the second.

Instances

GenMorph DB m1 m2 => Morph m1 m2

Methods

morph :: m1 a -> m2 a