Copyright | (c) 2008--2010 Universiteit Utrecht |
---|---|
License | BSD3 |
Maintainer | generics@haskell.org |
Stability | experimental |
Portability | non-portable |
Safe Haskell | Safe |
Language | Haskell2010 |
The definition of functorial map.
Generic map
class HFunctor phi f where Source #
hmapA :: Applicative a => (forall ix. phi ix -> r ix -> a (r' ix)) -> phi ix -> f r ix -> a (f r' ix) Source #
HFunctor phi U Source # | |
HFunctor phi (K x) Source # | |
El phi xi => HFunctor phi (I xi) Source # | |
(Constructor c, HFunctor phi f) => HFunctor phi (C c f) Source # | |
(Traversable f, HFunctor phi g) => HFunctor phi ((:.:) f g) Source # | |
HFunctor phi f => HFunctor phi ((:>:) f ix) Source # | |
(HFunctor phi f, HFunctor phi g) => HFunctor phi ((:*:) f g) Source # | |
(HFunctor phi f, HFunctor phi g) => HFunctor phi ((:+:) f g) Source # | |
hmap :: HFunctor phi f => (forall ix. phi ix -> r ix -> r' ix) -> phi ix -> f r ix -> f r' ix Source #
The function hmap
takes a functor f
. All the recursive instances
in that functor are wrapped by an application of r
. The argument to
hmap
takes a function that transformes r
occurrences into r'
occurrences, for every ix
. In order to associate the index ix
with the correct family phi
, the argument to hmap
is additionally
parameterized by a witness of type phi ix
.