Comment by LightMachine

No, I mean that users should choose whether they use lazy cloning or immutable references when sharing arguments, just like you have the choice for several pointer types in Rust. I don't think compilers should make that decision, since I like to have full control over my program's runtime costs. When compiling a language like Haskell to HVM, we can just use references by default, and lazy cloning could be opt-in (using some newtype or similar).