diff --git a/gnu/packages/haskell-xyz.scm b/gnu/packages/haskell-xyz.scm index 686b898b2f..cef3261f45 100644 --- a/gnu/packages/haskell-xyz.scm +++ b/gnu/packages/haskell-xyz.scm @@ -7137,6 +7137,42 @@ With it, you can determine the type of a file by examining its contents rather than its name.") (license license:bsd-3))) +(define-public ghc-managed + (package + (name "ghc-managed") + (version "1.0.6") + (source + (origin + (method url-fetch) + (uri (string-append + "mirror://hackage/package/managed/managed-" + version + ".tar.gz")) + (sha256 + (base32 + "1kbrw99yh5x5blykmx2n88mplbbi4ss1ij5j17b7asw6q0ihm9zi")))) + (build-system haskell-build-system) + (home-page "http://hackage.haskell.org/package/managed") + (synopsis "Monad for managed values") + (description + "In Haskell you very often acquire values using the with... idiom using +functions of type (a -> IO r) -> IO r. This idiom forms a Monad, which is a +special case of the ContT monad (from transformers) or the Codensity +monad (from kan-extensions). The main purpose behind this package is to +provide a restricted form of these monads specialized to this unusually common +case. + +The reason this package defines a specialized version of these types +is to: + +@itemize +@item be more beginner-friendly, +@item simplify inferred types and error messages, and: +@item provide some additional type class instances that would otherwise be +orphan instances +@end itemize") + (license license:bsd-3))) + (define-public ghc-markdown-unlit (package (name "ghc-markdown-unlit")