# Difference between revisions of "Zygohistomorphic prepromorphisms"

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<pre> | <pre> | ||

+ | import Control.Morphism.Zygo | ||

+ | import Control.Morphism.Prepro | ||

+ | import Control.Morphism.Histo | ||

+ | import Control.Functor.Algebra | ||

+ | |||

zygohistomorphic_prepromorphism :: Algebra f b -> GAlgebra f (Cofree f) a -> (f :~> f) -> FixF f -> a | zygohistomorphic_prepromorphism :: Algebra f b -> GAlgebra f (Cofree f) a -> (f :~> f) -> FixF f -> a | ||

zygohistomorphic_prepromorphism f = g_prepro (distZygoT (liftAlgebra f) (distHisto id)) -- unless you want a generalized zygomorphism. | zygohistomorphic_prepromorphism f = g_prepro (distZygoT (liftAlgebra f) (distHisto id)) -- unless you want a generalized zygomorphism. | ||

</pre> | </pre> |

## Revision as of 01:38, 9 June 2008

Used when you really need both semi-mutual recursion and history and to repeatedly apply a natural transformation as you get deeper into the functor.

import Control.Morphism.Zygo import Control.Morphism.Prepro import Control.Morphism.Histo import Control.Functor.Algebra zygohistomorphic_prepromorphism :: Algebra f b -> GAlgebra f (Cofree f) a -> (f :~> f) -> FixF f -> a zygohistomorphic_prepromorphism f = g_prepro (distZygoT (liftAlgebra f) (distHisto id)) -- unless you want a generalized zygomorphism.