Difference between revisions of "Zygohistomorphic prepromorphisms"
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| Line 2: | Line 2: | ||
<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.