You can of course use arenas in Rust just like in C. I think the parent was talking about support for using arenas as the memory for stuff like built-in containers (dynamic arrays, hash maps, etc.):

https://github.com/rust-lang/wg-allocators

Thank you! Yeah, something like bumpalo would work just fine right now but for the future this is a great interface:

https://docs.rs/bumpalo/latest/bumpalo/#nightly-rust-allocat...

  use bumpalo::Bump;
  
  let bump = Bump::new();
  
  let mut v = Vec::new_in(&bump);
  v.push(0);
  v.push(1);
  v.push(2);