Several TH/quasiquote changes

[ghc-hetmet.git] / compiler / rename / RnPat.lhs

diff --git a/compiler/rename/RnPat.lhs b/compiler/rename/RnPat.lhs
index 6367255..bc17495 100644 (file)
--- a/compiler/rename/RnPat.lhs
+++ b/compiler/rename/RnPat.lhs
@@ -11,7 +11,7 @@ free variables.
 
 \begin{code}
 module RnPat (-- main entry points
-              rnPats, rnBindPat,
+              rnPat, rnPats, rnBindPat,
 
               NameMaker, applyNameMaker,     -- a utility for making names:
               localRecNameMaker, topRecNameMaker,  --   sometimes we want to make local names,
@@ -22,9 +22,6 @@ module RnPat (-- main entry points
              -- Literals
              rnLit, rnOverLit,     
 
-             -- Quasiquotation
-             rnQuasiQuote,
-
              -- Pattern Error messages that are also used elsewhere
              checkTupSize, patSigErr
              ) where
@@ -133,9 +130,11 @@ which is how you go from a RdrName to a Name
 data NameMaker 
   = LamMk      -- Lambdas 
       Bool     -- True <=> report unused bindings
+               --   (even if True, the warning only comes out 
+               --    if -fwarn-unused-matches is on)
 
   | LetMk       -- Let bindings, incl top level
-               -- Do not check for unused bindings
+               -- Do *not* check for unused bindings
       (Maybe Module)   -- Just m  => top level of module m
                        -- Nothing => not top level
       MiniFixityEnv
@@ -146,8 +145,14 @@ topRecNameMaker mod fix_env = LetMk (Just mod) fix_env
 localRecNameMaker :: MiniFixityEnv -> NameMaker
 localRecNameMaker fix_env = LetMk Nothing fix_env 
 
-matchNameMaker :: NameMaker
-matchNameMaker = LamMk True
+matchNameMaker :: HsMatchContext a -> NameMaker
+matchNameMaker ctxt = LamMk report_unused
+  where
+    -- Do not report unused names in interactive contexts
+    -- i.e. when you type 'x <- e' at the GHCi prompt
+    report_unused = case ctxt of
+                      StmtCtxt GhciStmt -> False
+                      _                 -> True
 
 newName :: NameMaker -> Located RdrName -> CpsRn Name
 newName (LamMk report_unused) rdr_name
@@ -212,8 +217,8 @@ rnPats ctxt pats thing_inside
          -- (0) bring into scope all of the type variables bound by the patterns
          -- (1) rename the patterns, bringing into scope all of the term variables
          -- (2) then do the thing inside.
-       ; bindPatSigTyVarsFV (collectSigTysFromPats pats) $ 
-         unCpsRn (rnLPatsAndThen matchNameMaker pats)    $ \ pats' -> do
+       ; bindPatSigTyVarsFV (collectSigTysFromPats pats)     $ 
+         unCpsRn (rnLPatsAndThen (matchNameMaker ctxt) pats) $ \ pats' -> do
         { -- Check for duplicated and shadowed names 
                 -- Because we don't bind the vars all at once, we can't
                 --     check incrementally for duplicates; 
@@ -225,6 +230,12 @@ rnPats ctxt pats thing_inside
   where
     doc_pat = ptext (sLit "In") <+> pprMatchContext ctxt
 
+rnPat :: HsMatchContext Name -- for error messages
+      -> LPat RdrName 
+      -> (LPat Name -> RnM (a, FreeVars))
+      -> RnM (a, FreeVars)
+rnPat ctxt pat thing_inside 
+  = rnPats ctxt [pat] (\[pat'] -> thing_inside pat')
 
 applyNameMaker :: NameMaker -> Located RdrName -> RnM Name
 applyNameMaker mk rdr = do { (n, _fvs) <- runCps (newName mk rdr); return n }
@@ -355,8 +366,7 @@ rnPatAndThen _ p@(QuasiQuotePat {})
   = pprPanic "Can't do QuasiQuotePat without GHCi" (ppr p)
 #else
 rnPatAndThen mk (QuasiQuotePat qq)
-  = do { qq' <- liftCpsFV $ rnQuasiQuote qq
-       ; pat <- liftCps $ runQuasiQuotePat qq'
+  = do { pat <- liftCps $ runQuasiQuotePat qq
        ; L _ pat' <- rnLPatAndThen mk pat
        ; return pat' }
 #endif         /* GHCI */
@@ -557,27 +567,6 @@ rnOverLit lit@(OverLit {ol_val=val})
 
 %************************************************************************
 %*                                                                     *
-\subsubsection{Quasiquotation}
-%*                                                                     *
-%************************************************************************
-
-See Note [Quasi-quote overview] in TcSplice.
-
-\begin{code}
-rnQuasiQuote :: HsQuasiQuote RdrName -> RnM (HsQuasiQuote Name, FreeVars)
-rnQuasiQuote (HsQuasiQuote n quoter quoteSpan quote)
-  = do { loc  <- getSrcSpanM
-       ; n' <- newLocalBndrRn (L loc n)
-       ; 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
-       ; return (HsQuasiQuote n' quoter' quoteSpan quote, unitFV quoter') }
-\end{code}
-
-%************************************************************************
-%*                                                                     *
 \subsubsection{Errors}
 %*                                                                     *
 %************************************************************************