[Tuna-Fish]

Reflection is typically provided by a runtime, and languages that don't have runtimes usually don't have it. You shouldn't expect a low-level systems language to have reflection. There is no zero-cost way of implementing it.

[Joker_vD]

Except Rust has runtime: [0]. And so, usually, does C (in hosted implementations).

[0] https://doc.rust-lang.org/reference/runtime.html

[pornel]

These are a couple of functions executables can call at run time, but they're more like an extra standard library. It's not a runtime in the same sense as a runtime in dynamic or GC languages that manages all objects and is able to know types of arbitrary objects and inspect/trace them.

Rust has no run-time type information except limited downcasts via `dyn Any` or explicitly derived traits on per-type basis, and these features compile to type-specific monomorphic code rather than calling some run-time reflection.

[throwaway894345]

Pretty sure you don’t need a runtime to track runtime type info. What we think of as a “runtime” in GC languages is usually several distinct things (a scheduler, a GC, and maybe some other stuff in the case of Java/.Net).

[spacechild1]

This is of course only true for runtime reflection. And which language does not have a runtime?