From e3f95eb9a8b6978ffc2ff2b460e70f1c38cd17a7 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Fri, 19 May 2017 12:09:49 -0400
Subject: [PATCH] Define Language as a GADT.

---
 src/Language.hs | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/Language.hs b/src/Language.hs
index b0d0e19bb..cf38f7207 100644
--- a/src/Language.hs
+++ b/src/Language.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE DataKinds, GADTs #-}
 module Language where
 
 import Data.Record
@@ -9,12 +9,12 @@ import qualified Syntax as S
 import Term
 
 -- | A programming language.
-data Language =
-      C
-    | Go
-    | Markdown
-    | Ruby
-    | TypeScript -- ^ Also JavaScript.
+data Language where
+  C :: Language
+  Go :: Language
+  Markdown :: Language
+  Ruby :: Language
+  TypeScript :: Language -- ^ Also JavaScript.
     deriving (Show, Eq, Read)
 
 -- | Returns a Language based on the file extension (including the ".").