Why does D not have generics?

[Ola Fosheim Grøstad]

On Tuesday, 12 January 2021 at 17:32:17 UTC, Paul Backus wrote:
> template<MyConcept T>
> void fun(T t) { t.bar(); }
>
> In Java or Rust, the above would be a compile-time error.

Ok, I get what you say. Concepts is more for library implementors 
than applications, so it is assumed the library implementor knows 
what he is doing, and the focus is on putting restrictions on 
library usage.


But you can do that in C++ to some extent. You can remove members 
from a declaration, even though they are present in the 
definition. Thanks to header files and reinterpret casting. There 
is a lot of stuff you can do in C++ (but not really recommended).