05/08: gnu: Add ghc-fail.

[Ricardo Wurmus]

rekado pushed a commit to branch master
in repository guix.

commit 005a08e3dc41d28ecf5a11a8ca479044b82c4a6a
Author: Alex Vong <address@hidden>
Date:   Mon Aug 7 15:13:42 2017 +0800

    gnu: Add ghc-fail.
    
    * gnu/packages/haskell.scm (ghc-fail): New variable.
    
    Signed-off-by: Ricardo Wurmus <address@hidden>
---
 gnu/packages/haskell.scm | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/gnu/packages/haskell.scm b/gnu/packages/haskell.scm
index 552c57d..7085385 100644
--- a/gnu/packages/haskell.scm
+++ b/gnu/packages/haskell.scm
@@ -3970,6 +3970,30 @@ a subset of @code{MonadBase} into which generic control 
operations such as
 @code{catch} can be lifted from @code{IO} or any other base monad.")
     (license license:bsd-3)))
 
+(define-public ghc-fail
+  (package
+    (name "ghc-fail")
+    (version "4.9.0.0")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (string-append "https://hackage.haskell.org/package/fail/fail-";
+                           version ".tar.gz"))
+       (sha256
+        (base32 "18nlj6xvnggy61gwbyrpmvbdkq928wv0wx2zcsljb52kbhddnp3d"))))
+    (build-system haskell-build-system)
+    (home-page "https://prime.haskell.org/wiki/Libraries/Proposals/MonadFail";)
+    (synopsis "Forward-compatible MonadFail class")
+    (description
+     "This package contains the @code{Control.Monad.Fail} module providing the
address@hidden://prime.haskell.org/wiki/Libraries/Proposals/MonadFail, 
MonadFail}
+class that became available in
address@hidden://hackage.haskell.org/package/base-4.9.0.0, base-4.9.0.0} for
+older @code{base} package versions.  This package turns into an empty package
+when used with GHC versions which already provide the
address@hidden module.")
+    (license license:bsd-3)))
+
 (define-public ghc-byteorder
   (package
     (name "ghc-byteorder")