The Borrow Checker and Rapid Prototyping
How would you feel about a language that has a borrow checker with a prototyping mode for rapid iteration? In this mode, proper annotations would still be required (failure to do so would result in compile errors) because the compiler still needs that information to reason about lifetimes, but violations of the rules themselves would result in warnings. Compiling in safe mode would be just like Rust, resulting in errors.
Do you think this would meaningfully improve iteration times for domains which require it (game dev, for example)?
Would this defeat the purpose of a borrow checker, in that most would follow the path of least resistance and not bother to clean up after themselves, resulting in an ecosystem of unsafe libraries?