@hackage/semigroups0.20

Anything that associates

semigroups

Hackage Build Status

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.

Data.Semigroup and Data.List.NonEmpty were added to base as of 4.9.0.0. This package now offers a backwards-compatible API and some tools for deriving semigroups with generics.

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

  • Installation

  • Tested Compilers

  • Dependencies (15)

  • Dependents (979)

    @hackage/commonmark-pandoc, @hackage/Advise-me, @hackage/semigroupoids, @hackage/haskey-btree, @hackage/stgi, @hackage/svfactor, Show all…
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      hashable
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