// Copyright 2013 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. use std::cell::RefCell; fn main() { let m = RefCell::new(0); let mut b = m.borrow_mut(); let b1 = b.get(); let b2 = b.get(); //~ ERROR cannot borrow }