C++ or D?

[Paulo Pinto]

On Thursday, 24 December 2020 at 08:36:54 UTC, RSY wrote:
> On Wednesday, 23 December 2020 at 19:00:14 UTC, evilrat wrote:
>> On Wednesday, 23 December 2020 at 18:03:56 UTC, frame wrote:
>>>
>>> It's not the problem mentioned but I had to struggle with 
>>> DLLs and D's Variant-type. The problem is that Variant uses 
>>> TypeInfo which does not pass DLL boundaries correctly so that 
>>> int != int in runtime even it's in fact a simple int.
>>>
>>> If you need to exchange unknown data between a DLL and your 
>>> application you need to get a workaround and cannot use that 
>>> elsewhere settled nice feature. But it's a Windows specific 
>>> issue - it works as expected on other systems.
>>
>> Which is basically same as in C++, despite the fact it does 
>> have real working SO/DLL runtime's many large projects have 
>> their own RTTI implementation. LLVM has its own RTTI because 
>> standard type info is "inefficient", Unreal Engine has its 
>> own, IIRC Qt too has its own, etc...
>>
>> Same thing with D Variant, some people say it is 
>> "inefficient"... so we ended up having multiple libraries.
>>
>> Not saying anything about how good or bad all this, just the 
>> facts.
>
> C++ you need to write duplicate code (.h and .cpp)
>
> C++ you need to care about header include order
>
> C++ you need to forward declare everything you gonna use if it 
> is not included before
>
> C++ you need to waste time waiting for compile
>

Fixed with C++20 modules.

I am already playing with the experimental support on VC++.

> C++ you need to fight to get proper reflection
>

Coming in C++23, and partially available already with a mix of 
type traits and constexpr.


I am all good for D vs C++, but one needs to update their 
knowledge specially when the audience is up to date with latest 
ISO C++'s capabilities.