You make use of 'owned', 'shared', 'unmanaged', 'borrowed'.

https://chapel-lang.org/docs/language/spec/classes.html#clas...

I see, seems like the design is not complete and a work in progress (which is the same for Mojos Origins concept I think):

"The details of lifetime checking are not yet finalized or specified. Additional syntax to specify the lifetimes of function returns will probably be needed."

I think Rust proved that lifetimes, ownership and borrow checking can be useful for a mainstream language. The discussions in the Mojo context revolve on how to improve the ergonomics of these versus Rust.