[bug#44174] [PATCH 01/16] gnu: Add ghc-control-monad-free.

[Carlo Holl]

---
 gnu/packages/haskell-xyz.scm | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/gnu/packages/haskell-xyz.scm b/gnu/packages/haskell-xyz.scm
index 5b9da15630..ccbe026142 100644
--- a/gnu/packages/haskell-xyz.scm
+++ b/gnu/packages/haskell-xyz.scm
@@ -2608,6 +2608,37 @@ a vocabulary for working with them.")
 @code{ghc-contravariant} package.")
     (license license:expat)))
 
+(define-public ghc-control-monad-free
+  (package
+    (name "ghc-control-monad-free")
+    (version "0.6.2")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (string-append
+             
"https://hackage.haskell.org/package/control-monad-free/control-monad-free-";
+             version
+             ".tar.gz"))
+       (sha256
+        (base32
+         "1habgf7byffqf1rqjkzpihvdhclaafgqsqpfpwp3fgpj5ayk1j33"))))
+    (build-system haskell-build-system)
+    (home-page
+     "https://github.com/pepeiborra/control-monad-free";)
+    (synopsis "Free monads and monad transformers")
+    (description "This package provides datatypes to construct Free monads,
+Free monad transformers, and useful instances.  In addition it provides the
+constructs to avoid quadratic complexity of left associative bind, as 
explained in:
+
+@itemize @bullet
+@item
+Janis Voigtlander, @cite{Asymptotic Improvement of Computations over
+Free Monads, MPC'08}
+@end itemize
+
+")
+    (license license:public-domain)))
+
 (define-public ghc-convertible
   (package
     (name "ghc-convertible")
-- 
2.28.0