39/154: gnu: Add ghc-logict.

[Paul]

toothbrush pushed a commit to branch wip-haskell-platform-7.10.2-a
in repository guix.

commit 8a9938a6da79072c4e7483d46a05c43cd887747a
Author: Paul van der Walt <address@hidden>
Date:   Thu Oct 15 21:10:24 2015 +0200

    gnu: Add ghc-logict.
    
    * gnu/packages/haskell.scm (ghc-logict): New variable.
---
 gnu/packages/haskell.scm |   25 +++++++++++++++++++++++++
 1 files changed, 25 insertions(+), 0 deletions(-)

diff --git a/gnu/packages/haskell.scm b/gnu/packages/haskell.scm
index 1775e8e..0d28fd6 100644
--- a/gnu/packages/haskell.scm
+++ b/gnu/packages/haskell.scm
@@ -1053,6 +1053,31 @@ of functions that implement regular expression pattern 
matching using the same
 syntax and semantics as Perl 5.")
     (license bsd-3)))
 
+(define-public ghc-logict
+  (package
+    (name "ghc-logict")
+    (version "0.6.0.2")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (string-append
+             "http://hackage.haskell.org/package/logict/logict-";
+             version
+             ".tar.gz"))
+       (sha256
+        (base32
+         "07hnirv6snnym2r7iijlfz00b60jpy2856zvqxh989q0in7bd0hi"))))
+    (build-system haskell-build-system)
+    (inputs `(("ghc-mtl" ,ghc-mtl)))
+    (home-page "http://code.haskell.org/~dolio/";)
+    (synopsis "Backtracking logic-programming monad")
+    (description "This library provides a continuation-based, backtracking,
+logic programming monad.  An adaptation of the two-continuation implementation
+found in the paper \"Backtracking, Interleaving, and Terminating Monad
+Transformers\" available @uref{http://okmij.org/ftp/papers/LogicT.pdf,
+online}.")
+    (license bsd-3)))
+
 (define-public ghc-exceptions
   (package
     (name "ghc-exceptions")