> However even Rust thought Rust has lots of tools for preventing concurrency issues, it still doesn't have builtin ways for easy concurrent programs - and e.g.

> However even Rust thought Rust has lots of tools for preventing concurrency issues, it still doesn't have builtin ways for easy concurrent programs - and e.g. for solving the problem that is described in the article. Rust's Mutex type seems like it would be a good fit for this situation. Also this kind of callback -- which is executed immediately instead of stored and executed later -- doesn't require any heap allocation. You find callbacks like this in e.g. the scoped threading or rayon::join APIs.