@hackage semigroups0.14
Anything that associates
Categories
License
BSD-3-Clause
Maintainer
Edward A. Kmett <ekmett@gmail.com>
Links
Versions
Installation
Dependencies (8)
- base >=2 && <5
- bytestring >=0.9 && <1
- containers >=0.3 && <0.6
- ghc-prim
- hashable >=1.1 && <1.3
- nats >=0.1 && <1 Show all…
Dependents (1011)
@hackage/OpenSCAD, @hackage/Cabal, @hackage/qrcode-core, @hackage/theatre, @hackage/unity-testresult-parser, @hackage/comfort-graph, Show all…
Package Flags
hashable
(on by default)
You can disable the use of the hashable package using `-f-hashable`.
Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
If set we will not supply instances of Hashable
Note: `-f-hashable` implies `-f-unordered-containers`, as we are necessarily not able to supply those instances as well.
bytestring
(on by default)
You can disable the use of the bytestring package using `-f-bytestring`.
Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
containers
(on by default)
You can disable the use of the containers package using `-f-containers`.
Disabing this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
text
(on by default)
You can disable the use of the text package using `-f-text`.
Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
unordered-containers
(on by default)
You can disable the use of the `unordered-containers` package using `-f-unordered-containers`.
Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
semigroups
Haskellers are usually familiar with monoids. A monoid has an appending operation <> or mappend and an identity element mempty. A Semigroup has an append <>, but does not require an mempty element. A Monoid can be made a Semigroup with just instance Semigroup MyMonoid
More formally, a semigroup is an algebraic structure consisting of a set together with an associative binary operation. A semigroup generalizes a monoid in that there might not exist an identity element. It also (originally) generalized a group (a monoid with all inverses) to a type where every element did not have to have an inverse, thus the name semigroup.
Semigroups appear all over the place, except in the Haskell Prelude, so they are packaged here.
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