[cvs-nhc98] No log message

[Malcolm Wallace]

malcolm: Thu Oct  4 16:10:55 CEST 2001

Update of /usr/src/master/nhc/src/compiler98
In directory hinken:/tmp/cvs-serv11197

Modified Files:
	IExtract.hs Import.hs Main.hs MainNew.hs Need.hs PreImport.hs 
	Rename.hs RenameLib.hs 
Log Message:
Fix several serious bugs in the import mechanism.

  A module A which imported another module B both qualified and
  unqualified got very confused about what names were visible, and what
  could be re-exported.  The reason was that the qualified/unqualified
  distinction was being applied per module, not per identifier.

  A module containing imports such as
      import B (y)
      import B hiding (x)
  was being rejected with the spurious error that using both explicit
  imports and explicit hidings is not permitted.

  An implicit
      import qualified Prelude
  was being (incorrectly) added to all modules.

Some bugs still remain for now: it is not possible to import or
export only some constructors of a type / fields of a type / methods
of a class.  Either you get all of them or none of them.