[project @ 2002-12-10 15:27:58 by simonpj]

Report TH errors better in stage 1

diff --git a/ghc/compiler/rename/RnEnv.lhs b/ghc/compiler/rename/RnEnv.lhs
index 77e02b2..4f2fc94 100644 (file)
--- a/ghc/compiler/rename/RnEnv.lhs
+++ b/ghc/compiler/rename/RnEnv.lhs
@@ -581,19 +581,32 @@ implicitModuleFVs source_fvs
     namesNeededForFlattening           `plusFV`
     ubiquitousNames
 
+
+thProxyName :: NameSet
+mkTemplateHaskellFVs :: NameSet -> NameSet
        -- This is a bit of a hack.  When we see the Template-Haskell construct
        --      [| expr |]
        -- we are going to need lots of the ``smart constructors'' defined in
        -- the main Template Haskell data type module.  Rather than treat them
        -- all as free vars at every occurrence site, we just make the Q type
        -- consructor a free var.... and then use that here to haul in the others
-mkTemplateHaskellFVs source_fvs
+
 #ifdef GHCI
-       -- Only if Template Haskell is enabled
+---------------        Template Haskell enabled --------------
+thProxyName = unitFV qTyConName
+
+mkTemplateHaskellFVs source_fvs
   | qTyConName `elemNameSet` source_fvs = templateHaskellNames
-#endif
   | otherwise                          = emptyFVs
 
+#else
+---------------        Template Haskell disabled --------------
+
+thProxyName                    = emptyFVs
+mkTemplateHaskellFVs source_fvs = emptyFVs
+#endif
+--------------------------------------------------------
+
 -- ubiquitous_names are loaded regardless, because 
 -- they are needed in virtually every program
 ubiquitousNames 

diff --git a/ghc/compiler/rename/RnExpr.lhs b/ghc/compiler/rename/RnExpr.lhs
index b1481e3..e8e3f4f 100644 (file)
--- a/ghc/compiler/rename/RnExpr.lhs
+++ b/ghc/compiler/rename/RnExpr.lhs
@@ -43,9 +43,6 @@ import PrelNames      ( hasKey, assertIdKey,
                          crossPName, zipPName, toPName,
                          enumFromToPName, enumFromThenToPName, assertErrorName,
                          negateName, monadNames, mfixName )
-#ifdef GHCI
-import DsMeta          ( qTyConName )
-#endif
 import Name            ( Name, nameOccName )
 import NameSet
 import UnicodeUtil     ( stringToUtf8 )
@@ -227,30 +224,26 @@ rnExpr (HsPar e)
     returnM (HsPar e', fvs_e)
 
 -- Template Haskell extensions
-#ifdef GHCI
-rnExpr (HsBracket br_body loc)
-  = addSrcLoc loc                      $
-    checkGHCI (thErr "bracket")                `thenM_`
-    rnBracket br_body                  `thenM` \ (body', fvs_e) ->
-    returnM (HsBracket body' loc, fvs_e `addOneFV` qTyConName)
-       -- We use the Q tycon as a proxy to haul in all the smart
-       -- constructors; see the hack in RnIfaces
-
-rnExpr (HsSplice n e loc)
-  = addSrcLoc loc                      $
-    checkGHCI (thErr "splice")         `thenM_`
-    newLocalsRn [(n,loc)]              `thenM` \ [n'] ->
-    rnExpr e                           `thenM` \ (e', fvs_e) ->
-    returnM (HsSplice n' e' loc, fvs_e `addOneFV` qTyConName)
-       -- The qTyCon brutally pulls in all the meta stuff
-
-rnExpr (HsReify (Reify flavour name))
-  = checkGHCI (thErr "reify")          `thenM_`
-    lookupGlobalOccRn name             `thenM` \ name' ->
+-- Don't ifdef-GHCI them because we want to fail gracefully
+-- (not with an rnExpr crash) in a stage-1 compiler.
+rnExpr e@(HsBracket br_body loc)
+  = addSrcLoc loc              $
+    checkTH e "bracket"                `thenM_`
+    rnBracket br_body          `thenM` \ (body', fvs_e) ->
+    returnM (HsBracket body' loc, fvs_e `plusFV` thProxyName)
+
+rnExpr e@(HsSplice n splice loc)
+  = addSrcLoc loc              $
+    checkTH e "splice"         `thenM_`
+    newLocalsRn [(n,loc)]      `thenM` \ [n'] ->
+    rnExpr splice              `thenM` \ (splice', fvs_e) ->
+    returnM (HsSplice n' splice' loc, fvs_e `plusFV` thProxyName)
+
+rnExpr e@(HsReify (Reify flavour name))
+  = checkTH e "reify"          `thenM_`
+    lookupGlobalOccRn name     `thenM` \ name' ->
        -- For now, we can only reify top-level things
-    returnM (HsReify (Reify flavour name'), mkFVs [name', qTyConName])
-       -- The qTyCon brutally pulls in all the meta stuff
-#endif
+    returnM (HsReify (Reify flavour name'), unitFV name' `plusFV` thProxyName)
 
 rnExpr section@(SectionL expr op)
   = rnExpr expr                                        `thenM` \ (expr', fvs_expr) ->
@@ -917,9 +910,14 @@ doStmtListErr do_or_lc e
                        MDoExpr -> "mdo"
                        other   -> "do"
 
-thErr what
-  = ptext SLIT("Template Haskell") <+> text what <+>  
-    ptext SLIT("illegal in a stage-1 compiler") 
+#ifdef GHCI 
+checkTH e what = returnRn ()   -- OK
+#else
+checkTH e what         -- Raise an error in a stage-1 compiler
+  = addErr (vcat [ptext SLIT("Template Haskell") <+> text what <+>  
+                 ptext SLIT("illegal in a stage-1 compiler"),
+                 nest 2 (ppr e)])
+#endif   
 
 badIpBinds binds
   = hang (ptext SLIT("Implicit-parameter bindings illegal in a parallel list comprehension:")) 4