Unexpected productivity boost of Rust

Most of these productivity gains are achievable in any Standard ML influenced type system.

The example that the article gives relies on the borrow checker, which is not part of the usual Standard ML type system.

It is called affine type system, and there are ML descendents with it.

You can even go more crazy with linear types, effects, formal proofs or dependent types.

What Rust has achieved, was definitely make these ideas more mainstream.