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| -rw-r--r-- | gnu/packages/haskell-xyz.scm | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/gnu/packages/haskell-xyz.scm b/gnu/packages/haskell-xyz.scm index a34dcde389..a42baebde6 100644 --- a/gnu/packages/haskell-xyz.scm +++ b/gnu/packages/haskell-xyz.scm @@ -11398,6 +11398,40 @@ semigroup.") ghc-unordered-containers-bootstrap ghc-hashable-bootstrap)) (properties '((hidden? #t))))) +(define-public ghc-semirings + (package + (name "ghc-semirings") + (version "0.6") + (source + (origin + (method url-fetch) + (uri (string-append + "https://hackage.haskell.org/package/semirings/semirings-" + version + ".tar.gz")) + (sha256 + (base32 "16q535bvjl7395sqkx6zlw48y4fzr7irp44pcp7w9irpn4cncdcr")))) + (build-system haskell-build-system) + (inputs + (list ghc-base-compat-batteries ghc-hashable ghc-unordered-containers)) + (arguments + `(#:cabal-revision + ("1" "1c06yhfa053sv3rfz0d72a33l5qb0xmj1b3hy2z7pzxrcay6g1yc"))) + (home-page "https://github.com/chessai/semirings") + (synopsis "Two monoids as one, in holy haskimony") + (description + "Haskellers are usually familiar with monoids and semigroups. A monoid has an +appending operation @code{<>} (or @code{mappend}), and an identity element, +@code{mempty}. A semigroup has an appending @code{<>} operation, but does not +require a @code{mempty} element. A Semiring has two appending operations, +@code{plus} and @code{times}, and two respective identity elements, +@code{zero} and @code{one}. More formally, a Semiring R is a set equipped +with two binary relations @code{+} and @code{*}, such that: (R,+) is a +commutative monoid with identity element 0, (R,*) is a monoid with identity +element 1, (*) left and right distributes over addition, and . multiplication +by @code{0} annihilates R.") + (license license:bsd-3))) + (define-public ghc-serialise (package (name "ghc-serialise") |