From a6a4c8a8cc89b3ea664367163886fa712ff80a8f Mon Sep 17 00:00:00 2001
From: "simonpj@microsoft.com" <unknown>
Date: Tue, 14 Sep 2010 11:36:41 +0000
Subject: [PATCH] Comments only

---
 compiler/coreSyn/CoreSyn.lhs |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/compiler/coreSyn/CoreSyn.lhs b/compiler/coreSyn/CoreSyn.lhs
index 2ad111f..e09e4f2 100644
--- a/compiler/coreSyn/CoreSyn.lhs
+++ b/compiler/coreSyn/CoreSyn.lhs
@@ -536,8 +536,11 @@ The instance translates to
 Now we might encounter (op (dfCList {ty} d) a1 a2)
 and we want the (op (dfList {ty} d)) rule to fire, because $dfCList
 has all its arguments, even though its (value) arity is 2.  That's
-why we cache the number of expected 
+why we record the number of expected arguments in the DFunUnfolding.
 
+Note that although it's an Arity, it's most convenient for it to give
+the *total* number of arguments, both type and value.  See the use
+site in exprIsConApp_maybe.
 
 \begin{code}
 -- Constants for the UnfWhen constructor
-- 
1.7.10.4