From e2b2c4b9920dd7ca74c9e62640647c78848b162c Mon Sep 17 00:00:00 2001
From: "audreyt@audreyt.org" <unknown>
Date: Sat, 23 Sep 2006 05:09:29 +0000
Subject: [PATCH] Add explicit eta-reduction to GHCI's schemeE such that
 deriving Typeable won't panick.

---
 compiler/ghci/ByteCodeGen.lhs |    7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/compiler/ghci/ByteCodeGen.lhs b/compiler/ghci/ByteCodeGen.lhs
index db4e18c..69fc148 100644
--- a/compiler/ghci/ByteCodeGen.lhs
+++ b/compiler/ghci/ByteCodeGen.lhs
@@ -427,6 +427,13 @@ schemeE d s p (AnnNote note (_, body))
 schemeE d s p (AnnCast (_, body) _)
    = schemeE d s p body
 
+-- XXX - audreyt - After FC landed, this case of explicit eta-reduction
+--       seems needed to make "data D = D deriving Typeable" work in GHCi.
+--       however, how did AnnLam with a var (LocalId) survive until this place?
+schemeE d s p (AnnLam var (_, AnnApp (_, body) (_, AnnVar inner)))
+   | var == inner
+   = schemeE d s p body
+
 schemeE d s p other
    = pprPanic "ByteCodeGen.schemeE: unhandled case" 
                (pprCoreExpr (deAnnotate' other))
-- 
1.7.10.4