No longer any need to explicitly load module interface in 'toCore'

[matthijs/master-project/cλash.git] / HsTools.hs

diff --git a/HsTools.hs b/HsTools.hs
index ae5582a002f1c2f2d8d3685d5cfafe1216d369c1..d132ce874033020c12071996e3c112ec92477ce7 100644 (file)
--- a/HsTools.hs
+++ b/HsTools.hs
@@ -3,7 +3,7 @@ module HsTools where
 
 -- Standard modules
 import qualified Unsafe.Coerce
-
+import qualified Maybe
 
 -- GHC API
 import qualified GHC
@@ -14,6 +14,7 @@ import qualified FastString
 import qualified StringBuffer
 import qualified MonadUtils
 import Outputable ( showSDoc, ppr )
+import qualified Outputable
 -- Lexer & Parser, i.e. up to HsExpr
 import qualified Lexer
 import qualified Parser
@@ -24,19 +25,26 @@ import qualified HsExpr
 import qualified HsTypes
 import qualified HsBinds
 import qualified TcRnMonad
+import qualified TcRnTypes
 import qualified RnExpr
 import qualified RnEnv
 import qualified TcExpr
 import qualified TcEnv
 import qualified TcSimplify
+import qualified TcTyFuns
 import qualified Desugar
+import qualified InstEnv
+import qualified FamInstEnv
 import qualified PrelNames
 import qualified Module
 import qualified OccName
 import qualified RdrName
 import qualified Name
+import qualified TysWiredIn
 import qualified SrcLoc
+import qualified LoadIface
 import qualified BasicTypes
+import qualified Bag
 -- Core representation and handling
 import qualified CoreSyn
 import qualified Id
@@ -59,7 +67,9 @@ import CoreShow
 --    (==) = Prelude.(==) Int $dInt 
 --  in 
 --    \x = (==) x 1
-toCore :: HsSyn.HsExpr RdrName.RdrName -> GHC.Ghc CoreSyn.CoreExpr
+toCore ::
+  HsSyn.HsExpr RdrName.RdrName -- ^ The expression to translate to Core.
+  -> GHC.Ghc CoreSyn.CoreExpr -- ^ The resulting core expression.
 toCore expr = do
   env <- GHC.getSession
   let icontext = HscTypes.hsc_IC env
@@ -111,17 +121,33 @@ mkId rdr_name = do
         TcEnv.tcLookupId name 
   return id
 
+normaliseType ::
+  HscTypes.HscEnv
+  -> Type.Type
+  -> IO Type.Type
+normaliseType env ty = do
+   (err, nty) <- MonadUtils.liftIO $
+     -- Initialize the typechecker monad
+     TcRnMonad.initTcPrintErrors env PrelNames.iNTERACTIVE $ do
+       -- Normalize the type
+       (_, nty) <- TcTyFuns.tcNormaliseFamInst ty
+       return nty
+   let normalized_ty = Maybe.fromJust nty
+   return normalized_ty
+
 -- | Translate a core Type to an HsType. Far from complete so far.
 coreToHsType :: Type.Type -> HsTypes.LHsType RdrName.RdrName
 --  Translate TyConApps
-coreToHsType (Type.splitTyConApp_maybe -> Just (tycon, tys)) =
-  foldl (\t a -> SrcLoc.noLoc $ HsTypes.HsAppTy t a) tycon_ty (map coreToHsType tys)
-  where
-    tycon_name = TyCon.tyConName tycon
-    mod_name = Module.moduleName $ Name.nameModule tycon_name
-    occ_name = Name.nameOccName tycon_name
-    tycon_rdrname = RdrName.mkRdrQual mod_name occ_name
-    tycon_ty = SrcLoc.noLoc $ HsTypes.HsTyVar tycon_rdrname
+coreToHsType ty = case Type.splitTyConApp_maybe ty of
+  Just (tycon, tys) ->
+    foldl (\t a -> SrcLoc.noLoc $ HsTypes.HsAppTy t a) tycon_ty (map coreToHsType tys)
+    where
+      tycon_name = TyCon.tyConName tycon
+      mod_name = Module.moduleName $ Name.nameModule tycon_name
+      occ_name = Name.nameOccName tycon_name
+      tycon_rdrname = RdrName.mkRdrQual mod_name occ_name
+      tycon_ty = SrcLoc.noLoc $ HsTypes.HsTyVar tycon_rdrname
+  Nothing -> error $ "HsTools.coreToHsType Cannot translate non-tycon type"
 
 -- | Evaluate a CoreExpr and return its value. For this to work, the caller
 --   should already know the result type for sure, since the result value is
@@ -141,22 +167,6 @@ execCore expr = do
         let res = Unsafe.Coerce.unsafeCoerce hval :: Int
         return $ Unsafe.Coerce.unsafeCoerce hval
 
--- | Evaluate a core Type representing type level int from the TypeLevel
--- library to a real int.
-eval_type_level_int :: Type.Type -> Int
-eval_type_level_int ty =
-  unsafeRunGhc $ do
-    -- Automatically import modules for any fully qualified identifiers
-    setDynFlag DynFlags.Opt_ImplicitImportQualified
-
-    let to_int_name = mkRdrName "Data.TypeLevel.Num.Sets" "toInt"
-    let to_int = SrcLoc.noLoc $ HsExpr.HsVar to_int_name
-    let undef = hsTypedUndef $ coreToHsType ty
-    let app = HsExpr.HsApp (to_int) (undef)
-
-    core <- toCore app
-    execCore core 
-
 -- These functions build (parts of) a LHSExpr RdrName.
 
 -- | A reference to the Prelude.undefined function.
@@ -185,3 +195,30 @@ hscParseThing parser dflags str = do
     let Lexer.POk _ thing = Lexer.unP parser (Lexer.mkPState buf loc dflags)
     return thing
 
+-- | This function imports the module with the given name, for the renamer /
+-- typechecker to use. It also imports any "orphans" and "family instances"
+-- from modules included by this module, but not the actual modules
+-- themselves. I'm not 100% sure how this works, but it seems that any
+-- functions defined in included modules are available just by loading the
+-- original module, and by doing this orphan stuff, any (type family or class)
+-- instances are available as well.
+--
+-- Most of the code is based on tcRnImports and rnImportDecl, but those
+-- functions do a lot more (which I hope we won't need...).
+importModule :: Module.ModuleName -> TcRnTypes.RnM ()
+importModule mod = do
+  let reason = Outputable.text "Hardcoded import" -- Used for trace output
+  let pkg = Nothing
+  -- Load the interface.
+  iface <- LoadIface.loadSrcInterface reason mod False pkg
+  -- Load orphan an familiy instance dependencies as well. I think these
+  -- dependencies are needed for the type checker to know all instances. Any
+  -- other instances (on other packages) are only useful to the
+  -- linker, so we can probably safely ignore them here. Dependencies within
+  -- the same package are also listed in deps, but I'm not so sure what to do
+  -- with them.
+  let deps = HscTypes.mi_deps iface
+  let orphs = HscTypes.dep_orphs deps
+  let finsts = HscTypes.dep_finsts deps
+  LoadIface.loadOrphanModules orphs False
+  LoadIface.loadOrphanModules finsts True