-- These imports are the reason that TcSplice
-- is very high up the module hierarchy
-import qualified Language.Haskell.TH.THSyntax as TH
+import qualified Language.Haskell.TH as TH
-- THSyntax gives access to internal functions and data types
+import qualified Language.Haskell.TH.Syntax as TH
-import HscTypes ( HscEnv(..) )
-import HsSyn ( HsBracket(..), HsExpr(..), LHsExpr, LHsDecl )
-import Convert ( convertToHsExpr, convertToHsDecls )
+import HsSyn ( HsBracket(..), HsExpr(..), HsSplice(..), LHsExpr, LHsDecl,
+ HsType, LHsType )
+import Convert ( convertToHsExpr, convertToHsDecls, convertToHsType )
import RnExpr ( rnLExpr )
-import RnEnv ( lookupFixityRn )
+import RnEnv ( lookupFixityRn, lookupSrcOcc_maybe )
+import RdrName ( RdrName, mkRdrUnqual, lookupLocalRdrEnv )
+import RnTypes ( rnLHsType )
import TcExpr ( tcCheckRho, tcMonoExpr )
import TcHsSyn ( mkHsLet, zonkTopLExpr )
import TcSimplify ( tcSimplifyTop, tcSimplifyBracket )
import TcUnify ( Expected, zapExpectedTo, zapExpectedType )
-import TcType ( TcType, openTypeKind, mkAppTy, tcSplitSigmaTy )
+import TcType ( TcType, TcKind, liftedTypeKind, mkAppTy, tcSplitSigmaTy )
import TcEnv ( spliceOK, tcMetaTy, bracketOK, tcLookup )
-import TcMType ( newTyVarTy, UserTypeCtxt(ExprSigCtxt), zonkTcType, zonkTcTyVar )
-import TcHsType ( tcHsSigType )
+import TcMType ( newTyVarTy, newKindVar, UserTypeCtxt(ExprSigCtxt), zonkTcType, zonkTcTyVar )
+import TcHsType ( tcHsSigType, kcHsType )
import TypeRep ( Type(..), PredType(..), TyThing(..) ) -- For reification
-import Name ( Name, NamedThing(..), nameOccName, nameModule, isExternalName )
+import Name ( Name, NamedThing(..), nameOccName, nameModule, isExternalName, mkInternalName )
import OccName
import Var ( Id, TyVar, idType )
-import RdrName ( RdrName )
import Module ( moduleUserString, mkModuleName )
import TcRnMonad
import IfaceEnv ( lookupOrig )
import TysWiredIn ( mkListTy )
import DsMeta ( expQTyConName, typeQTyConName, decTyConName, qTyConName, nameTyConName )
import ErrUtils ( Message )
-import SrcLoc ( noLoc, unLoc )
+import SrcLoc ( noLoc, unLoc, getLoc, noSrcLoc )
import Outputable
-import Unique ( Unique, Uniquable(..), getKey )
-import IOEnv ( IOEnv )
+import Unique ( Unique, Uniquable(..), getKey, mkUniqueGrimily )
+
import BasicTypes ( StrictnessMark(..), Fixity(..), FixityDirection(..) )
-import Module ( moduleUserString )
import Panic ( showException )
import FastString ( LitString )
-import FastTypes ( iBox )
-import GHC.Base ( unsafeCoerce#, Int(..) ) -- Should have a better home in the module hierarchy
+import GHC.Base ( unsafeCoerce#, Int#, Int(..) ) -- Should have a better home in the module hierarchy
import Monad ( liftM )
+
+#ifdef GHCI
+import FastString ( mkFastString )
+#endif
\end{code}
\begin{code}
tcSpliceDecls :: LHsExpr Name -> TcM [LHsDecl RdrName]
-
-tcSpliceExpr :: Name
- -> LHsExpr Name
- -> Expected TcType
- -> TcM (HsExpr Id)
+tcSpliceExpr :: HsSplice Name -> Expected TcType -> TcM (HsExpr TcId)
+kcSpliceType :: HsSplice Name -> TcM (HsType Name, TcKind)
#ifndef GHCI
tcSpliceExpr n e ty = pprPanic "Cant do tcSpliceExpr without GHCi" (ppr e)
-- Result type is Var (not Q-monadic)
tc_bracket (ExpBr expr)
- = newTyVarTy openTypeKind `thenM` \ any_ty ->
+ = newTyVarTy liftedTypeKind `thenM` \ any_ty ->
tcCheckRho expr any_ty `thenM_`
tcMetaTy expQTyConName
-- Result type is Expr (= Q Exp)
%************************************************************************
\begin{code}
-tcSpliceExpr name expr res_ty
- = getStage `thenM` \ level ->
+tcSpliceExpr (HsSplice name expr) res_ty
+ = addSrcSpan (getLoc expr) $
+ getStage `thenM` \ level ->
case spliceOK level of {
Nothing -> failWithTc (illegalSplice level) ;
Just next_level ->
-- Here (h 4) :: Q Exp
-- but $(h 4) :: forall a.a i.e. anything!
- zapExpectedType res_ty `thenM_`
+ zapExpectedType res_ty liftedTypeKind `thenM_`
tcMetaTy expQTyConName `thenM` \ meta_exp_ty ->
setStage (Splice next_level) (
setLIEVar lie_var $
%************************************************************************
%* *
+ Splicing a type
+%* *
+%************************************************************************
+
+Very like splicing an expression, but we don't yet share code.
+
+\begin{code}
+kcSpliceType (HsSplice name hs_expr)
+ = addSrcSpan (getLoc hs_expr) $ do
+ { level <- getStage
+ ; case spliceOK level of {
+ Nothing -> failWithTc (illegalSplice level) ;
+ Just next_level -> do
+
+ { case level of {
+ Comp -> do { (t,k) <- kcTopSpliceType hs_expr
+ ; return (unLoc t, k) } ;
+ Brack _ ps_var lie_var -> do
+
+ { -- A splice inside brackets
+ ; meta_ty <- tcMetaTy typeQTyConName
+ ; expr' <- setStage (Splice next_level) $
+ setLIEVar lie_var $
+ tcCheckRho hs_expr meta_ty
+
+ -- Write the pending splice into the bucket
+ ; ps <- readMutVar ps_var
+ ; writeMutVar ps_var ((name,expr') : ps)
+
+ -- e.g. [| Int -> $(h 4) |]
+ -- Here (h 4) :: Q Type
+ -- but $(h 4) :: forall a.a i.e. any kind
+ ; kind <- newKindVar
+ ; returnM (panic "kcSpliceType", kind) -- The returned type is ignored
+ }}}}}
+
+kcTopSpliceType :: LHsExpr Name -> TcM (LHsType Name, TcKind)
+kcTopSpliceType expr
+ = do { meta_ty <- tcMetaTy typeQTyConName
+
+ -- Typecheck the expression
+ ; zonked_q_expr <- tcTopSpliceExpr expr meta_ty
+
+ -- Run the expression
+ ; traceTc (text "About to run" <+> ppr zonked_q_expr)
+ ; simple_ty <- runMetaT zonked_q_expr
+
+ ; let -- simple_ty :: TH.Type
+ hs_ty2 :: LHsType RdrName
+ hs_ty2 = convertToHsType simple_ty
+
+ ; traceTc (text "Got result" <+> ppr hs_ty2)
+
+ ; showSplice "type" zonked_q_expr (ppr hs_ty2)
+
+ -- Rename it, but bale out if there are errors
+ -- otherwise the type checker just gives more spurious errors
+ ; let doc = ptext SLIT("In the spliced type") <+> ppr hs_ty2
+ ; hs_ty3 <- checkNoErrs (rnLHsType doc hs_ty2)
+
+ ; kcHsType hs_ty3 }
+\end{code}
+
+%************************************************************************
+%* *
\subsection{Splicing an expression}
%* *
%************************************************************************
\begin{code}
-- Always at top level
tcSpliceDecls expr
- = tcMetaTy decTyConName `thenM` \ meta_dec_ty ->
- tcMetaTy qTyConName `thenM` \ meta_q_ty ->
- let
- list_q = mkAppTy meta_q_ty (mkListTy meta_dec_ty)
- in
- tcTopSpliceExpr expr list_q `thenM` \ zonked_q_expr ->
-
- -- Run the expression
- traceTc (text "About to run" <+> ppr zonked_q_expr) `thenM_`
- runMetaD zonked_q_expr `thenM` \ simple_expr ->
- -- simple_expr :: [TH.Dec]
- -- decls :: [RdrNameHsDecl]
- handleErrors (convertToHsDecls simple_expr) `thenM` \ decls ->
- traceTc (text "Got result" <+> vcat (map ppr decls)) `thenM_`
- showSplice "declarations"
- zonked_q_expr (vcat (map ppr decls)) `thenM_`
- returnM decls
+ = do { meta_dec_ty <- tcMetaTy decTyConName
+ ; meta_q_ty <- tcMetaTy qTyConName
+ ; let list_q = mkAppTy meta_q_ty (mkListTy meta_dec_ty)
+ ; zonked_q_expr <- tcTopSpliceExpr expr list_q
+
+ -- Run the expression
+ ; traceTc (text "About to run" <+> ppr zonked_q_expr)
+ ; simple_expr <- runMetaD zonked_q_expr
+
+ -- simple_expr :: [TH.Dec]
+ -- decls :: [RdrNameHsDecl]
+ ; decls <- handleErrors (convertToHsDecls simple_expr)
+ ; traceTc (text "Got result" <+> vcat (map ppr decls))
+ ; showSplice "declarations"
+ zonked_q_expr (vcat (map ppr decls))
+ ; returnM decls }
where handleErrors :: [Either a Message] -> TcM [a]
handleErrors [] = return []
-> TcM TH.Exp -- Of type Exp
runMetaE e = runMeta e
-runMetaD :: LHsExpr Id -- Of type Q [Dec]
+runMetaT :: LHsExpr Id -- Of type (Q Type)
+ -> TcM TH.Type -- Of type Type
+runMetaT e = runMeta e
+
+runMetaD :: LHsExpr Id -- Of type Q [Dec]
-> TcM [TH.Dec] -- Of type [Dec]
runMetaD e = runMeta e
\begin{code}
reify :: TH.Name -> TcM TH.Info
-reify (TH.Name occ (TH.NameG th_ns mod))
- = do { name <- lookupOrig (mkModuleName (TH.modString mod))
- (OccName.mkOccName ghc_ns (TH.occString occ))
+reify th_name
+ = do { name <- lookupThName th_name
; thing <- tcLookup name
+ -- ToDo: this tcLookup could fail, which would give a
+ -- rather unhelpful error message
; reifyThing thing
}
+
+lookupThName :: TH.Name -> TcM Name
+lookupThName (TH.Name occ (TH.NameG th_ns mod))
+ = lookupOrig (mkModuleName (TH.modString mod))
+ (OccName.mkOccName ghc_ns (TH.occString occ))
where
ghc_ns = case th_ns of
TH.DataName -> dataName
TH.TcClsName -> tcClsName
TH.VarName -> varName
+lookupThName th_name@(TH.Name occ TH.NameS)
+ = do { let rdr_name = mkRdrUnqual (OccName.mkOccFS ns occ_fs)
+ ; rdr_env <- getLocalRdrEnv
+ ; case lookupLocalRdrEnv rdr_env rdr_name of
+ Just name -> return name
+ Nothing -> do
+ { mb_name <- lookupSrcOcc_maybe rdr_name
+ ; case mb_name of
+ Just name -> return name ;
+ Nothing -> failWithTc (notInScope th_name)
+ }}
+ where
+ ns | isLexCon occ_fs = OccName.dataName
+ | otherwise = OccName.varName
+ occ_fs = mkFastString (TH.occString occ)
+
+lookupThName (TH.Name occ (TH.NameU uniq))
+ = return (mkInternalName (mk_uniq uniq) (OccName.mkOccFS bogus_ns occ_fs) noSrcLoc)
+ where
+ occ_fs = mkFastString (TH.occString occ)
+ bogus_ns = OccName.varName -- Not yet recorded in the TH name
+ -- but only the unique matters
+
+mk_uniq :: Int# -> Unique
+mk_uniq u = mkUniqueGrimily (I# u)
+
+notInScope :: TH.Name -> SDoc
+notInScope th_name = quotes (text (show (TH.ppr th_name))) <+>
+ ptext SLIT("is not in scope at a reify")
+ -- Ugh! Rather an indirect way to display the name
+
------------------------------
reifyThing :: TcTyThing -> TcM TH.Info
-- The only reason this is monadic is for error reporting,
projects / ghc-hetmet.git / blobdiff