[commit: ghc] master: Comments only (c5f43e5)

[Simon Peyton Jones]

Repository : http://darcs.haskell.org/ghc.git/

On branch  : master

https://github.com/ghc/ghc/commit/c5f43e5f1f3f78661e9e8a137b4fec6eef1e47a2

>---------------------------------------------------------------

commit c5f43e5f1f3f78661e9e8a137b4fec6eef1e47a2
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Sat Apr 6 21:24:37 2013 +0100

    Comments only

>---------------------------------------------------------------

 compiler/typecheck/TcSimplify.lhs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/compiler/typecheck/TcSimplify.lhs b/compiler/typecheck/TcSimplify.lhs
index c0cdb75..6d153ca 100644
--- a/compiler/typecheck/TcSimplify.lhs
+++ b/compiler/typecheck/TcSimplify.lhs
@@ -375,8 +375,10 @@ having to be passed at each call site.  But of course, the WHOLE
 IDEA is that ?y should be passed at each call site (that's what
 dynamic binding means) so we'd better infer the second.
 
-BOTTOM LINE: when *inferring types* you *must* quantify 
-over implicit parameters. See the predicate isFreeWhenInferring.
+BOTTOM LINE: when *inferring types* you must quantify over implicit
+parameters, *even if* they don't mention the bound type variables.
+Reason: because implicit parameters, uniquely, have local instance
+declarations. See the predicate quantifyPred.
 
 Note [Quantification with errors]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~