There is a Metal Obj-C API, Metal implementation is C++.
No it's not - the compiler for MSL is of course C++ because it's LLVM but the runtime is absolutely written in objc (there weren't even C++ bindings until recently).
No it's not - the compiler for MSL is of course C++ because it's LLVM but the runtime is absolutely written in objc (there weren't even C++ bindings until recently).