gnu: Add ghc-skylighting.

* gnu/packages/haskell.scm (ghc-skylighting): New variable.

gnu/packages/haskell.scm

@@ -5704,6 +5704,50 @@ needs.  It provides a very simple API to create sockets to a destination with
 the choice of SSL/TLS, and SOCKS.")
     (license license:bsd-3)))
 
+(define-public ghc-skylighting
+  (package
+    (name "ghc-skylighting")
+    (version "0.5.1")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append "https://hackage.haskell.org/package/skylighting-"
+                                  version "/skylighting-" version ".tar.gz"))
+              (sha256
+               (base32
+                "0l5lhhqqlfaq1fs7pn3n3b25kmazk8p4ahwvhagbrhcbm5hsigdg"))))
+    (build-system haskell-build-system)
+    (inputs
+     `(("ghc-aeson" ,ghc-aeson)
+       ("ghc-ansi-terminal" ,ghc-ansi-terminal)
+       ("ghc-attoparsec" ,ghc-attoparsec)
+       ("ghc-base64-bytestring" ,ghc-base64-bytestring)
+       ("ghc-blaze-html" ,ghc-blaze-html)
+       ("ghc-case-insensitive" ,ghc-case-insensitive)
+       ("ghc-colour" ,ghc-colour)
+       ("ghc-diff" ,ghc-diff)
+       ("ghc-hxt" ,ghc-hxt)
+       ("ghc-mtl" ,ghc-mtl)
+       ("ghc-pretty-show" ,ghc-pretty-show)
+       ("ghc-regex-pcre-builtin" ,ghc-regex-pcre-builtin)
+       ("ghc-safe" ,ghc-safe)
+       ("ghc-text" ,ghc-text)
+       ("ghc-utf8-string" ,ghc-utf8-string)))
+    (native-inputs
+     `(("ghc-hunit" ,ghc-hunit)
+       ("ghc-quickcheck" ,ghc-quickcheck)
+       ("ghc-tasty" ,ghc-tasty)
+       ("ghc-tasty-golden" ,ghc-tasty-golden)
+       ("ghc-tasty-hunit" ,ghc-tasty-hunit)
+       ("ghc-tasty-quickcheck" ,ghc-tasty-quickcheck)))
+    (home-page "https://hackage.haskell.org/package/skylighting")
+    (synopsis "Syntax highlighting library")
+    (description "Skylighting is a syntax highlighting library with support
+for over one hundred languages.  It derives its tokenizers from XML syntax
+definitions used by KDE's @code{KSyntaxHighlighting} framework, so any syntax
+supported by that framework can be added.  An optional command-line program is
+provided.  Skylighting is intended to be the successor to highlighting-kate.")
+    (license license:gpl2)))
+
 (define-public ghc-doctemplates
   (package
     (name "ghc-doctemplates")