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Date: Fri, 30 May 2003 11:51:45 -0400
From: Hyman Rosen <hyrosen@mail.com>
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Subject: Re: MI in Ada 200X
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Date: 2003-05-30T11:51:45-04:00
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Mark A. Biggar wrote:
> 1) does d contain 1 or 2 copies of the fields of a?
In C++ you choose, by specifying virtual inheritance or not.

> 2) if 2 how do you name them?
Do a view conversion to the appropriate base class.

> 3) which version of op does d inherit?
Neither. Attemping to call op on a d object would be a
compile-time error.

> 4) the simple implementation (TAG is pointer to vtable, field offsets
>     remain constant, etc.) becomes much more complicated.

Yes, but this is a job for the implementors, which they need
to do just once.