//@ edition:2021 //@ run-pass #![allow(unused)] // If the closures can handle such precision we should be able to read one path in the closure // while being able mutate another path outside the closure, where the two paths are disjoint // after applying two projections on the root variable. struct Point { x: i32, y: i32, } struct Wrapper { p: Point, } fn main() { let mut w = Wrapper { p: Point { x: 10, y: 10 } }; let c = || { println!("{}", w.p.x); }; // `c` only captures `w.p.x`, therefore it's safe to mutate `w.p.y`. let py = &mut w.p.y; c(); *py = 20 }