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Re: Generative record types
> From: "R. Kent Dybvig" <dyb@cs.indiana.edu>
> Subject: Re: Generative record types
> Date: Wed, 24 Apr 1996 16:44:40 -0500 (EST)
>
> > 1. I am in favor of opaque types, and object to the make-record-type
> > proposal on the grounds that it builds into the language support for
> > breaking abstractions. If we had a mechanism for specifying
> > programming environment support, abstraction breaking mechanisms would
> > be worth considering, but not as part of the language.
> >
> > [ ... ]
>
> > 2. I object to the procedural interface and prefer a syntactic
> > interface [ ... ]
Isn't this rather similar to the disagreement over macros?
Might it not be handled in a similar way? (A high-level, "right
semantics", interface, and then a lower, more open and procedural
level.)
I think I understand why some want to stop people from breaking
abstractions. But sometimes -- I'm sorry -- that's just what I
want to do. I've found it annoying, for instance, that in Common
Lisp that way to "break into" structs is implementation-specific.
Could we perhaps compromise by having a way to say whether a
particular struct type was opaque or not? Or would we then
fall out over the built-in types?
-- jeff