[project @ 1999-07-15 14:08:03 by keithw]

This commit makes a start at implementing polymorphic usage
annotations.

* The module Type has now been split into TypeRep, containing the
  representation Type(..) and other information for `friends' only,
  and Type, providing the public interface to Type.  Due to a bug in
  the interface-file slurping prior to ghc-4.04, {-# SOURCE #-}
  dependencies must unfortunately still refer to TypeRep even though
  they are not friends.

* Unfoldings in interface files now print as __U instead of __u.
  UpdateInfo now prints as __UA instead of __U.

* A new sort of variables, UVar, in their own namespace, uvName, has
  been introduced for usage variables.

* Usage binders __fuall uv have been introduced.  Usage annotations
  are now __u - ty (used once), __u ! ty (used possibly many times),
  __u uv ty (used uv times), where uv is a UVar.  __o and __m have
  gone.  All this still lives only in a TyNote, *for now* (but not for
  much longer).

* Variance calculation for TyCons has moved from
  typecheck/TcTyClsDecls to types/Variance.

* Usage annotation and inference are now done together in a single
  pass.  Provision has been made for inferring polymorphic usage
  annotations (with __fuall) but this has not yet been implemented.
  Watch this space!

1 files changed, 4 insertions, 2 deletions

diff --git a/ghc/compiler/cprAnalysis/CprAnalyse.lhs b/ghc/compiler/cprAnalysis/CprAnalyse.lhs
index 7cf43ca97c..6ad58cd05f 100644
--- a/ghc/compiler/cprAnalysis/CprAnalyse.lhs
+++ b/ghc/compiler/cprAnalysis/CprAnalyse.lhs
@@ -15,7 +15,7 @@ import Var		( Var, Id, TyVar, idType, varName, varType )
 import Id               ( setIdCprInfo, getIdCprInfo, getIdUnfolding )
 import IdInfo           ( CprInfo(..) )
 import VarEnv
-import Type             ( Type(..), splitFunTys, splitForAllTys, splitNewType_maybe ) 
+import Type             ( Type, splitFunTys, splitForAllTys, splitNewType_maybe )
 import TyCon            ( isProductTyCon, isNewTyCon, isUnLiftedTyCon )
 import DataCon          ( dataConTyCon, splitProductType_maybe )
 import Const            ( Con(DataCon), isWHNFCon )
@@ -365,8 +365,9 @@ splitTypeToFunArgAndRes ty = (tyvars, argtys, resty)
           (argtys, resty) = splitFunTysIgnoringNewTypes funty
 --          (argtys, resty) = splitFunTys funty
 
--- Taken from splitFunTys in Type.lhs.  Modified to keep searching through newtypes
+-- splitFunTys, modified to keep searching through newtypes.
 -- Should move to Type.lhs if it is doing something sensible.
+
 splitFunTysIgnoringNewTypes :: Type -> ([Type], Type)
 splitFunTysIgnoringNewTypes ty = split ty
   where
@@ -378,6 +379,7 @@ splitFunTysIgnoringNewTypes ty = split ty
 	     where
 		(args, res) = splitFunTys ty
 
+
 -- Is this the constructor for a product type (i.e. algebraic, single constructor) 
 -- NB: isProductTyCon replies 'False' for unboxed tuples
 isConProdType :: Con -> Bool