From 67264e748ad8075c7fb59529749c3b416b50c6bb Mon Sep 17 00:00:00 2001
From: Paul Chiusano <paul.chiusano@gmail.com>
Date: Tue, 1 Dec 2015 23:19:24 -0500
Subject: [PATCH] fix parenthesization bug in prettyprinters

---
 shared/src/Unison/Views.hs | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/shared/src/Unison/Views.hs b/shared/src/Unison/Views.hs
index a34874cb9..c83180a50 100644
--- a/shared/src/Unison/Views.hs
+++ b/shared/src/Unison/Views.hs
@@ -5,7 +5,6 @@
 module Unison.Views where
 
 import Data.List
-import Data.Maybe
 import Data.Map (Map)
 import Data.Text (Text)
 import Unison.Doc (Doc)
@@ -94,12 +93,13 @@ term ref t = go no View.low t where
         Symbol.Symbol _ name view = op fn
         (taken, remaining) = splitAt (View.arity view) args
         fmt (child,path) = (\p -> go (fn ==) p child, path)
-        applied = fromMaybe unsaturated (View.instantiate view fnP name (map fmt taken))
+        applied = maybe unsaturated (D.parenthesize (p > View.precedence view)) $
+                  View.instantiate view fnP name (map fmt taken)
         unsaturated = D.sub' fnP $ go no View.high fn
       in
         (if inChain fn then id else D.group) $ case remaining of
           [] -> applied
-          args -> D.parenthesize (p > View.high) . D.group . D.docs $
+          args -> D.group . D.docs $
             [ applied, D.breakable " "
             , D.nest "  " . D.group . D.delimit (D.breakable " ") $
               [ D.sub' p (go no (View.increase View.high) s) | (s,p) <- args ] ]
@@ -140,12 +140,13 @@ type' ref t = go no View.low t
         Symbol _ name view = op fn
         (taken, remaining) = splitAt (View.arity view) args
         fmt (child,path) = (\p -> D.sub' path (go (fn ==) p child), path)
-        applied = fromMaybe unsaturated (View.instantiate view fnP name (map fmt taken))
+        applied = maybe unsaturated (D.parenthesize (p > View.precedence view))
+                                    (View.instantiate view fnP name (map fmt taken))
         unsaturated = D.sub' fnP $ go no View.high fn
       in
         (if inChain fn then id else D.group) $ case remaining of
           [] -> applied
-          args -> D.parenthesize (p > View.high) . D.group . D.docs $
+          args -> D.group . D.docs $
             [ applied, D.breakable " "
             , D.nest "  " . D.group . D.delimit (D.breakable " ") $
               [ D.sub' p (go no (View.increase View.high) s) | (s,p) <- args ] ]