@@ 3390,6 3390,57 @@ forms of the Yoneda lemma, and (co)density (co)monads for Haskell.")
in the @code{IO} monad, like @code{IORef}s or parts of the OpenGL state.")
(license bsd-3)))
+(define-public ghc-lens
+ (package
+ (name "ghc-lens")
+ (version "4.13")
+ (source
+ (origin
+ (method url-fetch)
+ (uri (string-append
+ "http://hackage.haskell.org/package/lens/lens-"
+ version
+ ".tar.gz"))
+ (sha256
+ (base32
+ "0g4g0xksrb2m8wgsmraaq8qnk1sssb42kr65fc7clgyid6zyfmim"))))
+ (build-system haskell-build-system)
+ (arguments `(#:tests? #f)) ; FIXME: doctest packagedb propagation problem.
+ (propagated-inputs
+ `(("ghc-base-orphans" ,ghc-base-orphans)
+ ("ghc-bifunctors" ,ghc-bifunctors)
+ ("ghc-distributive" ,ghc-distributive)
+ ("ghc-exceptions" ,ghc-exceptions)
+ ("ghc-free" ,ghc-free)
+ ("ghc-kan-extensions" ,ghc-kan-extensions)
+ ("ghc-parallel" ,ghc-parallel)
+ ("ghc-reflection" ,ghc-reflection)
+ ("ghc-semigroupoids" ,ghc-semigroupoids)
+ ("ghc-vector" ,ghc-vector)))
+ (inputs
+ `(("ghc-comonad" ,ghc-comonad)
+ ("ghc-contravariant" ,ghc-contravariant)
+ ("ghc-hashable" ,ghc-hashable)
+ ("ghc-mtl" ,ghc-mtl)
+ ("ghc-profunctors" ,ghc-profunctors)
+ ("ghc-semigroups" ,ghc-semigroups)
+ ("ghc-tagged" ,ghc-tagged)
+ ("ghc-text" ,ghc-text)
+ ("ghc-transformers-compat" ,ghc-transformers-compat)
+ ("ghc-unordered-containers" ,ghc-unordered-containers)
+ ("ghc-void" ,ghc-void)
+ ("ghc-generic-deriving" ,ghc-generic-deriving)
+ ("ghc-nats" ,ghc-nats)
+ ("ghc-simple-reflect" ,ghc-simple-reflect)
+ ("hlint" ,hlint)))
+ (home-page "http://github.com/ekmett/lens/")
+ (synopsis "Lenses, Folds and Traversals")
+ (description "This library provides @code{Control.Lens}. The combinators
+in @code{Control.Lens} provide a highly generic toolbox for composing families
+of getters, folds, isomorphisms, traversals, setters and lenses and their
+indexed variants.")
+ (license bsd-3)))
+
(define-public ghc-tagsoup
(package
(name "ghc-tagsoup")