From 82897fa5e9b13ad386b6ef6e6bdb3d045a793a84 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Sun, 10 Sep 2017 21:41:41 -0400
Subject: [PATCH] Define a Pretty1 instance for BindingF.

---
 src/Data/Functor/Binding.hs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/Data/Functor/Binding.hs b/src/Data/Functor/Binding.hs
index dddf032ee..5e5b5759d 100644
--- a/src/Data/Functor/Binding.hs
+++ b/src/Data/Functor/Binding.hs
@@ -26,3 +26,9 @@ envLookup var = lookup var . unEnv
 
 instance Pretty Metavar where
   pretty (Metavar v) = pretty v
+
+instance Pretty1 f => Pretty1 (BindingF f) where
+  liftPretty p pl (Let vars body) = pretty ("let" :: String) <+> align (vsep (prettyKV <$> vars)) <> line
+                                 <> pretty ("in" :: String)  <+> liftPretty p pl body
+    where prettyKV (var, val) = pretty var <+> pretty '=' <+> p val
+  liftPretty _ _  (VarF metavar)  = pretty metavar