The functor-apply package
Deprecated in favor of semigroupoids
Provides a wide array of semigroup based Functors.
When working with comonads you often have the <*> portion of an Applicative, but not the pure. This was captured in Uustalu and Vene's "Essence of Dataflow Programming" in the form of the ComonadZip class in the days before Applicative. Apply provides a weaker invariant, but for the comonads used for data flow programming (found in the streams package), this invariant is preserved.
Ideally the following relationships would hold:
Traversable <---- Foldable <--- Functor ------> Alt ---------> Plus | | | | v v v v Traversable1 <--- Foldable1 Apply --------> Applicative -> Alternative | | | v v v Bind ---------> Monad -------> MonadPlus Bitraversable <-- Bifoldable <- Bifunctor Semigroupoid | | | | v v v v Bitraversable1 <- Bifoldable1 Biapply Category | v Arrow
This lets us remove many of the restrictions from various monad transformers as in many cases the binding operation or <*> operation does not require them.
Finally, to work with these weaker structures it is beneficial to have containers that can provide stronger guarantees about their contents, so versions of Traversable and Foldable that can be folded with just a Semigroup are added.
|Versions||0.5.0, 0.6.0, 0.7.0, 0.7.1, 0.7.2, 0.7.3, 0.7.4, 0.7.4.1, 0.9.0, 0.9.1, 0.9.2, 0.9.3, 0.10.0, 0.10.0.1, 0.10.0.2, 0.10.0.3, 0.10.1, 0.10.3, 0.10.4, 0.10.5, 0.11|
|Change log||None available|
|Dependencies||base (>=4 && <4.4), bifunctors (==0.1.*), comonad (>=0.9.0 && <1.0), containers (>=0.4.0 && <0.5), semigroups (>=0.3.2 && <0.4), transformers (>=0.2.0 && <0.3) [details]|
|Copyright||Copyright (C) 2011 Edward A. Kmett|
|Author||Edward A. Kmett|
|Maintainer||Edward A. Kmett <email@example.com>|
|Uploaded||Sun Jan 30 11:05:01 UTC 2011 by EdwardKmett|
|Downloads||2901 total (110 in last 30 days)|
|Status||Docs uploaded by user|
Build status unknown [no reports yet]
- functor-apply-0.10.3.tar.gz [browse] (Cabal source package)
- Package description (included in the package)
For package maintainers and hackage trustees