Making the macro more general?

[Boscop]

On the Rust discord, Yandros suggested this closure macro:
https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=a2addffcab2830703f08831f5887e191

It's more general than the current one of this crate, it allows capturing by any means,
so it also works for things like Arc::clone or by calling a custom cloning function (a = foo(a)) etc.