Presumably they'd freeze snapshots/versions of the behavior at various points in time, similar to https://doc.rust-lang.org/edition-guide/editions/index.html ht

Presumably they'd freeze snapshots/versions of the behavior at various points in time, similar to https://doc.rust-lang.org/edition-guide/editions/index.html https://doc.rust-lang.org/edition-guide/editions/index.html An analogy from the C++ world: In late 2016, there was an evolving C++17 specification, and the latest versions of gcc and clang were starting to implement C++17 behaviors. But you could read the C++14 specification to understand "this is what everyone agreed on in 2014", and invoke your compiler with the -std=c++14 flag to get that behavior. If you already had older software written against the C++11 spec, invoke your compiler with -std=c++11.