Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!fred
From: fred@cs.utexas.edu (Fred Hosch)
Newsgroups: comp.lang.ada
Subject: Re: Limited types and generic parameters
Message-ID: <4837@cs.utexas.edu>
Date: 22 Feb 89 14:58:49 GMT
References: <890222132712.21a009c0@elcc.epfl.ch>
Organization: U. Texas CS Dept., Austin, Texas
Lines: 31


Without careful scrutiny of the LRM (always a mistake), the only reasonable
semantics seem to be the following.

	The generic "entity" is interpreted in its defining environment;
	thus, any free variables occuring in the generic are bound in the
	context of the generic definition.

	The generic instantiation "returns" an entity that is bound in
	the instantiating environment; any generic formals are bound to
	actuals interpreted in the instantiating environment.

Thus in the example   

   generic
      type T is limited private;
   package GP is
      type R is
         record
            F : T;
         end record;
   end GP;

   package P is new GP(T => INTEGER);

P.R.F is of type INTEGER in the instantiating environment.

(At least, that's my state-educated guess.)

				Fred Hosch
				fred@cs.utexas.edu