X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcSplice.lhs;fp=compiler%2Ftypecheck%2FTcSplice.lhs;h=d114efb3aae5a003570bef0f1327abf78f56c1e5;hp=61ed8c7838f913b0a2aa8d97f766e48d33872b95;hb=eb07278946f1cec5e0c0a44a8b435950c62196f6;hpb=cfc8f7c2a49494d47d2966b310c5b3fbc2ae2499

diff --git a/compiler/typecheck/TcSplice.lhs b/compiler/typecheck/TcSplice.lhs
index 61ed8c7..d114efb 100644
--- a/compiler/typecheck/TcSplice.lhs
+++ b/compiler/typecheck/TcSplice.lhs
@@ -74,6 +74,7 @@ import BasicTypes
 import Panic
 import FastString
 import Exception
+import Control.Monad	( when )
 
 import qualified Language.Haskell.TH as TH
 -- THSyntax gives access to internal functions and data types
@@ -655,15 +656,16 @@ runQuasiQuote :: Outputable hs_syn
               -> RnM hs_syn
 runQuasiQuote (HsQuasiQuote quoter q_span quote) quote_selector meta_ty meta_ops
   = do	{ quoter' <- lookupOccRn quoter
-		-- If 'quoter' is not in scope, proceed no further
-		-- Otherwise lookupOcc adds an error messsage and returns 
-		-- an "unubound name", which makes the subsequent attempt to
-		-- run the quote fail
-		--
 		-- We use lookupOcc rather than lookupGlobalOcc because in the
 		-- erroneous case of \x -> [x| ...|] we get a better error message
 		-- (stage restriction rather than out of scope).
 
+        ; when (isUnboundName quoter') failM 
+		-- If 'quoter' is not in scope, proceed no further
+		-- The error message was generated by lookupOccRn, but it then
+		-- succeeds with an "unbound name", which makes the subsequent 
+		-- attempt to run the quote fail in a confusing way
+
           -- Check that the quoter is not locally defined, otherwise the TH
           -- machinery will not be able to run the quasiquote.
    	; this_mod <- getModule