From 82b1bc1f874bf65acd4281fb0a4b833e9f0484a1 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Mon, 14 Aug 2017 16:46:51 -0400
Subject: [PATCH] Define a helper to match context infix.

---
 src/Data/Syntax.hs | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/Data/Syntax.hs b/src/Data/Syntax.hs
index fe3dbc515..0441ec5b7 100644
--- a/src/Data/Syntax.hs
+++ b/src/Data/Syntax.hs
@@ -9,6 +9,7 @@ import Data.Align.Generic
 import Data.ByteString (ByteString)
 import qualified Data.Error as Error
 import Data.Foldable (toList)
+import Data.Function ((&))
 import Data.Ix
 import Data.List.NonEmpty (NonEmpty(..), nonEmpty)
 import Data.Functor.Classes.Eq.Generic
@@ -67,6 +68,14 @@ postContextualize context rule end = make <$> rule <*> Assignment.manyThrough co
           Just cs -> (makeTerm1 (Context cs node), end)
           _ -> (node, end)
 
+infixContext :: (Context :< fs, Alternative m, Semigroup a, HasCallStack, Apply1 Foldable fs)
+             => m (Term (Union fs) a)
+             -> m (Term (Union fs) a)
+             -> m (Term (Union fs) a)
+             -> [m (Term (Union fs) a -> Term (Union fs) a -> Union fs a)]
+             -> m (Union fs a)
+infixContext context left right operators = uncurry (&) <$> postContextualize context left (Assignment.choice operators) <*> right
+
 
 -- Undifferentiated