Why can't structs be derived from?

[Jens]

Steven Schveighoffer wrote:
> On Tue, 15 Mar 2011 15:28:09 -0400, Jens <jne at somewhere.org> wrote:
>
>> Steven Schveighoffer wrote:
>>> On Tue, 15 Mar 2011 14:54:13 -0400, Jens <jne at somewhere.org> wrote:
>>>
>>>> I didn't ask how to do composition in D. I asked why composition
>>>> cannot be done via derivation, i.e., the reasoning behind the
>>>> language design choice. A design faux paus IMO.
>>>
>>> Because composition by inheritance can be *completely* implemented
>>> using alias this -- a feature that also provides other niceties. Why 
>>> provide another mechanism to do the exact same thing, just
>>> because you are used to it?
>>
>> 1. I'm not convinced the other functionality is necessary.
>> 2. I eschew ugly syntax.
>
> Beauty is subjective, so I guess I can say at this point, go write
> your own language that is beautiful in your mind.  Good luck.
>

I am. Thanks.

>>
>>>
>>> Note that "inheritance" is actually done exactly this way in C++, by
>>> putting the derived type at the front of the "derived" type, and
>>> aliasing all the methods/fields into the derived namespace.
>>>
>>> Show me what composition by derivation provides that alias this does
>>> not.
>>
>> Nice syntax.
>
> So in other words, you want an aqua-blue bikeshed, when D's is just
> blue.
> This will be my last reply to this thread...
>

Aww, little boy didn't get his way and is going home to cry to mommy.