Thanks for bringing rust into the discussion - they handle language standardization/evolution very effectively, in my opinion. "Experimental" features are added

Thanks for bringing rust into the discussion - they handle language standardization/evolution very effectively, in my opinion. "Experimental" features are added to the language, but they are all effectively #define-gated for at least one release before being concretized (it's done more pragmatically than a literal #define of course, given that rust doesn't have any concept of #defines). This makes sense in my opinion because it gives an opportunity to evaluate proposed language changes under real-world use-cases before making it official, and people must explicitly opt into the possibility of their code not working with future releases, thus fully knowing and accepting the risks.