// Copyright 2012 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // 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. struct Rec { f: int } fn destructure(x: &mut Rec) { match *x { Rec {f: ref mut f} => *f += 1 } } fn main() { let mut v = Rec {f: 22}; destructure(&mut v); assert v.f == 23; }