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From: HABERNOL@DB0TUI11.BITNET (Thomas Habernoll)
Newsgroups: comp.lang.modula2
Subject: Re: Dereferencing of opaquely exported pointers?
Message-ID: <8709061851.AA10079@cayuga.cs.rochester.edu>
Date: Sun, 6-Sep-87 14:58:27 EDT
Article-I.D.: cayuga.8709061851.AA10079
Posted: Sun Sep  6 14:58:27 1987
Date-Received: Sun, 6-Sep-87 21:24:26 EDT
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>Assume that a module M1 exports a pointer type P opaquely, and a
>module M2 imports P from M1 and declares a variable p of type P.
>Can M2 refer to p^, new(p) and dispose(p) {allocate, or deallocate}?

How could you know anything about the implementation of an opaque type?
What lets you believe that it has to be a pointer type? (Yes, I know
there is a proposal to restrict opaque types to pointer types only.
But (1) this doesn't change the meaning of the word "opaque"
and (2) it is a proposal and current implementations don't have
this restriction).

  Thomas