Refactor SrcLoc and SrcSpan

[ghc-hetmet.git] / compiler / typecheck / TcRnMonad.lhs

diff --git a/compiler/typecheck/TcRnMonad.lhs b/compiler/typecheck/TcRnMonad.lhs
index bd48872..46624c5 100644 (file)
--- a/compiler/typecheck/TcRnMonad.lhs
+++ b/compiler/typecheck/TcRnMonad.lhs
@@ -406,7 +406,6 @@ traceRn, traceSplice :: SDoc -> TcRn ()
 traceRn      = traceOptTcRn Opt_D_dump_rn_trace
 traceSplice  = traceOptTcRn Opt_D_dump_splices
 
-
 traceIf, traceHiDiffs :: SDoc -> TcRnIf m n ()
 traceIf      = traceOptIf Opt_D_dump_if_trace
 traceHiDiffs = traceOptIf Opt_D_dump_hi_diffs
@@ -495,9 +494,10 @@ getSrcSpanM :: TcRn SrcSpan
 getSrcSpanM = do { env <- getLclEnv; return (tcl_loc env) }
 
 setSrcSpan :: SrcSpan -> TcRn a -> TcRn a
-setSrcSpan loc thing_inside
-  | isGoodSrcSpan loc = updLclEnv (\env -> env { tcl_loc = loc }) thing_inside
-  | otherwise        = thing_inside    -- Don't overwrite useful info with useless
+setSrcSpan loc@(RealSrcSpan _) thing_inside
+    = updLclEnv (\env -> env { tcl_loc = loc }) thing_inside
+-- Don't overwrite useful info with useless:
+setSrcSpan (UnhelpfulSpan _) thing_inside = thing_inside
 
 addLocM :: (a -> TcM b) -> Located a -> TcM b
 addLocM fn (L loc a) = setSrcSpan loc $ fn a
@@ -892,6 +892,9 @@ add_err_tcm tidy_env err_msg loc ctxt
 mkErrInfo :: TidyEnv -> [ErrCtxt] -> TcM SDoc
 -- Tidy the error info, trimming excessive contexts
 mkErrInfo env ctxts
+ | opt_PprStyle_Debug     -- In -dppr-debug style the output 
+ = return empty                  -- just becomes too voluminous
+ | otherwise
  = go 0 env ctxts
  where
    go :: Int -> TidyEnv -> [ErrCtxt] -> TcM SDoc