How to store a pointer to class contructor

[Dmitriy Asondo]

On Thursday, 24 December 2020 at 11:02:11 UTC, Mike Parker wrote:
> On Thursday, 24 December 2020 at 10:33:00 UTC, Dmitriy Asondo 
> wrote:
>> The idea is to store somewhere services (classes) first and 
>> only when the app need - instantiate services for 
>> app/thread/http-request (as option) and provide values to 
>> constructors via DI
>
> There's `Object.factory`, which constructs a class instance 
> from a fully-qualified name:
>
> https://dlang.org/phobos/object.html#.Object.factory
>
> But IIRC there are issues with it in some cases and I believe 
> it's supposed to be deprecated at some point.
>
> I'd just give the classes an interface and use function 
> pointers to construct them:
>
> ```
> interface IService { ... }
>
> alias ServiceMaker = IService function();
>
> ServiceMaker[string] serviceRegistry;
>
> class FooService : IService { ... }
> IService makeFooService() { return new FooService(); }
>
> void registerServices() {
>     serviceRegistry["FooService"] = &makeFooService;
> }
> ```


Hm... So, I need helpers like common interface for services & 
function-factory for every. It would be difficult to automate)


Ok, I see, thank you!

Is there any way, for example on compile step, to get class name 
from class pointer? To automate generation of factory via template