You can define a trait and add an blanket implementation of that trait for `Fn()` Somewhat like this: https://play.rust-lang.org/?version=stable&mode=debug&edi

You can define a trait and add an blanket implementation of that trait for `Fn()` Somewhat like this: https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=4c640afa36b18d956420dbce69a30de2 https://play.rust-lang.org/?version=stable&mode=debug&editio... Edit: updated playground link