[bug#38423] [PATCH 18/49] gnu: Add ghc-only.

[Robert Vollmert]

* gnu/packages/haskell-xyz.scm (ghc-only): New variable.
---
 gnu/packages/haskell-xyz.scm | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/gnu/packages/haskell-xyz.scm b/gnu/packages/haskell-xyz.scm
index 3eadfff08c..497ce4a5e6 100644
--- a/gnu/packages/haskell-xyz.scm
+++ b/gnu/packages/haskell-xyz.scm
@@ -13521,3 +13521,31 @@ ExceptT instances in scope.")
      "Better alternatives to the \"error\" function")
     (description "")
     (license license:expat)))
+
+(define-public ghc-only
+  (package
+    (name "ghc-only")
+    (version "0.1")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (string-append
+             "https://hackage.haskell.org/package/Only/Only-";
+             version
+             ".tar.gz"))
+       (sha256
+        (base32
+         "0rdj3a629fk2vp121jq8mf2smkblrz5w3cxhlsyx6my2x29s2ymb"))))
+    (build-system haskell-build-system)
+    (arguments
+     `(#:cabal-revision
+       ("1"
+        "1ahk7p34kmh041mz7lyc10nhcxgv2i4z8nvzxvqm2x34gslmsbzr")))
+    (home-page
+     "http://hackage.haskell.org/package/Only";)
+    (synopsis
+     "The 1-tuple type or single-value \"collection\"")
+    (description
+     "This package provides a canonical anonymous 1-tuple type missing from
+Haskell for attaching typeclass instances.")
+    (license license:bsd-3)))
-- 
2.21.0 (Apple Git-122.2)