// Copyright 2015 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. fn call_it(f: F) where F: Fn() { f(); } struct A; impl A { fn gen(&self) {} fn gen_mut(&mut self) {} } fn main() { let mut x = A; call_it(|| { //~ HELP consider changing this to accept closures that implement `FnMut` call_it(|| x.gen()); call_it(|| x.gen_mut()); //~ ERROR cannot borrow data mutably in a captured outer //~^ ERROR cannot borrow data mutably in a captured outer //~| HELP consider changing this closure to take self by mutable reference }); }