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From: jeenglis@nunki.usc.edu (Joe English)
Newsgroups: comp.lang.c++
Subject: Re: Variable sized objects
Message-ID: <6987@chaph.usc.edu>
Date: 11 Dec 89 22:15:13 GMT
References: <1262@amethyst.math.arizona.edu> <2240@dataio.Data-IO.COM>
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Reply-To: jeenglis@nunki.usc.edu (Joe English)
Organization: University of Southern California, Los Angeles, CA
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bright@dataio.Data-IO.COM (Walter Bright) writes:
>Variable sized objects are quite useful and work fine. The only thing
>you cannot do is derive from a variable size class.
>
>Does anyone know how to *prevent* a derivation from a particular class
>(i.e. cause a compile-time error if you try it)?

One way would be to add language support for variable-sized
objects by allowing zero-length arrays as the last
data member (and *only* as the last member) of a class.  
Then the compiler could take care of disallowing 
inheritance.

Then again, C++ already has enough tricky semantics...


--Joe English

  jeenglis@nunki.usc.edu