Re: [boost] Re: Re: is_base_and_derived question

From: David Abrahams (dave_at_[hidden])
Date: 2003-01-28 13:52:11

"Andrei Alexandrescu" <andrewalex_at_[hidden]> writes:

> "David Abrahams" <dave_at_[hidden]> wrote in message
> news:u3cndjmu6.fsf_at_boost-consulting.com...
>> > Yes, a class is it's own superclass/subclass, but IMO not it's own
>> > base: so it is a bug in the implementation.
>>
>> I'd like to suggest changing the documentation to match the
>> implementation at this point.  I know of a few places where I have
>> relied on the current semantics, and I'm sure that's the case for
>> others as well.  I'm not set on this course, but I think it's worth
>> considering.
>
> At the cost of adding an extra name, maybe it would be nice to provide
> is_base_and_derived and is_super_and_subclass.

I could get behind that if I could quickly tell the difference in
semantics from those names, but I can't.

Also, I think there's a principle behind the boost type traits that
they reflect standard notions of the type system, (which doesn't
include "subclass"), so by that logic my idea of keeping the semantics
and changing the docs also seems kinda bogus.  I guess I withdraw it.

-- 
                       David Abrahams
   dave_at_[hidden] * http://www.boost-consulting.com
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