free: Monads for free
Free monads are useful for many tree-like structures and domain specific languages.
If f is a Functor then the free Monad on f is the type
of trees whose nodes are labeled with the constructors of f. The word
"free" is used in the sense of "unrestricted" rather than "zero-cost":
Free f makes no constraining assumptions beyond those given by f and the
definition of Monad. As used here it is a standard term from the
mathematical theory of adjoint functors.
Cofree comonads are dual to free monads. They provide convenient ways to talk
about branching streams and rose-trees, and can be used to annotate syntax
trees. The cofree comonad can be seen as a stream parameterized by a Functor
that controls its branching factor.
More information on free monads, including examples, can be found in the following blog posts: http://comonad.com/reader/2008/monads-for-free/ http://comonad.com/reader/2011/free-monads-for-less/
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- free-5.1.9.tar.gz [browse] (Cabal source package)
- Package description (revised from the package)
Note: This package has metadata revisions in the cabal description newer than included in the tarball. To unpack the package including the revisions, use 'cabal get'.
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| Versions [RSS] | 0.1.0, 0.1.1, 0.2.0, 0.2.1, 0.2.2, 0.2.3, 1.8.0, 1.8.0.1, 1.8.0.3, 1.8.0.4, 2.0, 2.0.1, 2.0.1.1, 2.0.2, 2.0.3, 2.1, 2.1.1, 2.1.1.1, 2.2, 3.0, 3.1, 3.1.1, 3.2, 3.3, 3.3.0.1, 3.3.0.2, 3.3.1, 3.4, 3.4.1, 3.4.2, 4.0, 4.1, 4.2, 4.4, 4.5, 4.6, 4.6.1, 4.7, 4.7.1, 4.8, 4.8.0.1, 4.9, 4.10.0.1, 4.11, 4.12, 4.12.1, 4.12.2, 4.12.3, 4.12.4, 5, 5.0.1, 5.0.2, 5.1, 5.1.1, 5.1.2, 5.1.3, 5.1.4, 5.1.5, 5.1.6, 5.1.7, 5.1.8, 5.1.9, 5.1.10, 5.2 (info) |
|---|---|
| Change log | CHANGELOG.markdown |
| Dependencies | base (>=4.5 && <5), bifunctors (>=5.5.9 && <6), comonad (>=5.0.8 && <6), containers (>=0.3 && <0.7), distributive (>=0.5.2 && <1), exceptions (>=0.10.4 && <0.11), fail (>=4.9 && <4.10), indexed-traversable (>=0.1.1 && <0.2), mtl (>=2.1.3.1 && <2.4), profunctors (>=5.2.2 && <5.3 || >=5.6.1 && <6), semigroupoids (>=5.3.5 && <6), semigroups (>=0.18.5 && <1), template-haskell (>=2.7.0.0 && <2.20), th-abstraction (>=0.4.2.0 && <0.5), transformers (>=0.3 && <0.7), transformers-base (>=0.4.5.2 && <0.5), transformers-compat (>=0.5.1.0 && <0.8) [details] |
| Tested with | ghc ==7.4.2, ghc ==7.6.3, ghc ==7.8.4, ghc ==7.10.3, ghc ==8.0.2, ghc ==8.2.2, ghc ==8.4.4, ghc ==8.6.5, ghc ==8.8.4, ghc ==8.10.7, ghc ==9.0.2, ghc ==9.2.2 |
| License | BSD-3-Clause |
| Copyright | Copyright (C) 2008-2015 Edward A. Kmett |
| Author | Edward A. Kmett |
| Maintainer | Edward A. Kmett <ekmett@gmail.com> |
| Revised | Revision 1 made by ryanglscott at 2022-07-23T18:31:45Z |
| Category | Control, Monads |
| Home page | http://github.com/ekmett/free/ |
| Bug tracker | http://github.com/ekmett/free/issues |
| Source repo | head: git clone git://github.com/ekmett/free.git |
| Uploaded | by ryanglscott at 2022-06-26T16:02:11Z |
| Distributions | Arch:5.1.10, Debian:5.1.3, Fedora:5.1.10, FreeBSD:4.12.1, LTSHaskell:5.2, NixOS:5.2, Stackage:5.2, openSUSE:5.2 |
| Reverse Dependencies | 204 direct, 8020 indirect [details] |
| Downloads | 259396 total (514 in the last 30 days) |
| Rating | 2.5 (votes: 5) [estimated by Bayesian average] |
| Your Rating | |
| Status | Docs available [build log] Last success reported on 2022-06-26 [all 1 reports] |
Readme for free-5.1.9
[back to package description]free
This package provides a common definitions for working with free monads, free applicatives, and cofree comonads in Haskell.
Contact Information
Contributions and bug reports are welcome!
Please feel free to contact me through github or on the #haskell IRC channel on irc.freenode.net.
-Edward Kmett