// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. #![warn(clippy::temporary_assignment)] use std::ops::{Deref, DerefMut}; struct Struct { field: i32, } struct Wrapper<'a> { inner: &'a mut Struct, } impl<'a> Deref for Wrapper<'a> { type Target = Struct; fn deref(&self) -> &Struct { self.inner } } impl<'a> DerefMut for Wrapper<'a> { fn deref_mut(&mut self) -> &mut Struct { self.inner } } fn main() { let mut s = Struct { field: 0 }; let mut t = (0, 0); Struct { field: 0 }.field = 1; (0, 0).0 = 1; // no error s.field = 1; t.0 = 1; Wrapper { inner: &mut s }.field = 1; }