gnu: Add idris-wl-pprint.

* gnu/packages/idris.scm (idris-wl-pprint): New variable.

gnu/packages/idris.scm

@@ -179,3 +179,28 @@ Epigram and Agda.")
 by Parsec.  This package is used (almost) the same way as Parsec, except for one
 difference: backtracking.")
       (license license:bsd-2))))
+
+(define-public idris-wl-pprint
+  (let ((commit "1d365fcf4ba075859844dbc5eb96a90f57b9f338"))
+    (package
+      (name "idris-wl-pprint")
+      (version (git-version "0.1" "1" commit))
+      (source (origin
+                (method git-fetch)
+                (uri (git-reference
+                      (url "https://github.com/shayan-najd/wl-pprint")
+                      (commit commit)))
+                (file-name (git-file-name name version))
+                (sha256
+                 (base32
+                  "0g7c3y9smifdz4sivi3qmvymhdr7v9kfq45fmfmmvkqcrix0spzn"))))
+      (build-system gnu-build-system)
+      (native-inputs
+       `(("idris" ,idris)))
+      (arguments (idris-default-arguments name))
+      (home-page "https://github.com/shayan-najd/wl-pprint")
+      (synopsis "Pretty printing library")
+      (description "A pretty printing library for Idris based on Phil Wadler's
+paper A Prettier Printer and on Daan Leijen's extensions in the Haskell
+wl-pprint library.")
+      (license license:bsd-2))))