They just decided to release 1.0 without generics, instead of waiting for it to be 100% ready.
As Don clearly describes on his blog.
In fact, I'm a big fan of how Microsoft does versioning, supporting previous versions, but releasing major versions with backwards incompatible changes. You see this in DirectX, and IMO, that's why we're talking about DirectX and Vulkan, rather than AZDO OpenGL these days. It really gives you an opportunity to clean up the cruft.
Metal uses Objective-C/Swift, with shaders in C++14. The Objective-C runtime can be used as FFI.
DirectX, uses COM with HLSL (a C++ subset). Likewise any COM or .NET (via RCW) aware language can talk to it.
One of the reasons OpenCL lost to CUDA was being stuck with C, while CUDA offered C, C++, Fortran and any additional language that could target PTX.
Which was what eventually made them come up with SPIR and later SPIR-V.
NVN and LibCGNM are also based on C++ and C++ inspired shader languages.
All modern OO, with nice SDKs that handle font, texture, materials, maths, GPGPU debugging.
I wouldn't say "without many issues." It took a major surgery in the CLR codebase to add generics. The difference between CLR 1.1 without generics and CLR 2.0 with generics was huge. No area of code was untouched.
I was thinking of more fundamental changes to Java idiom and the standard library had generics been part of the design (e.g., how arrays work).
To the 2nd - The concrete types are separate, but they fit into a common interface hierarchy, so, at a source code level, they're plenty interoperable. For example, the (non-generic) IEnumerable interface has a Cast<T>() extension method that will convert it to a (generic) IEnumerable<T>. IEnumerable<T>, for its part, simply inherits IEnumerable.
In general, I actually like using those conversion methods for downcasting, because it gives a clearer indication of when I'm in a danger zone - for example, converting a non-generic list to a generic list might fail if the non-generic list contains a mix of different types of object. Java's situation feels less predictable to me, as this article illustrates fairly well. A few keystrokes for the sake of safer code is a dandy tradeoff in my book.
That's not true. (Mass shared hoster kinda guy here) when we pushed a bunch of customers code compiled for .NET 1.0/1.1 over to hosting environments with only CLR 2 available, their code ran just fine. These were .NET 1.0/1.1 assemblies.
There are some edge cases where stuff could break, say when doing reflection or emitting your own IL, but that for most LOB web hosted apps was pretty rare.
I did in fact marvel how backwards compatible CLR 2 was when it first shipped.
When there is a C# class that both has and doesn't have type information, they are actually completely different classes that just happen to share a base name.
This really made it painful when they first added generics. If you used generic containers but wanted to call into a library that predated it you hand to transform your data in/out of all the calls to the library. In Java land you didn't have to do anything other then a blind cast on the out side which doesn't even have a runtime penalty.
Long term the C# way was probably better but then they didn't have nearly as robust of a library ecosystem when they added generics.
In Java's case, old bytecode using Map would correctly work with change to Map <K, V>. C# introduced a new set of collections I believe.
Except for the fact that all CLR languages must adopt the same variance model, enforced by the runtime (or choose not to interoperate well).
Take a look at C# which added it without many issues (because they were willing to break back compat of their bytecode). Go fits this model a whole lot better.