// Copyright 2014 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. // Tests that a closure which requires mutable access to the referent // of an `&mut` requires a "unique" borrow -- that is, the variable to // be borrowed (here, `x`) will not be borrowed *mutably*, but // may be *immutable*, but we cannot allow // multiple borrows. fn get(x: &int) -> int { *x } fn set(x: &mut int) -> int { *x } fn a(x: &mut int) { let c1 = |&mut:| get(x); let c2 = |&mut:| get(x); } fn b(x: &mut int) { let c1 = |&mut:| get(x); let c2 = |&mut:| set(x); //~ ERROR closure requires unique access to `x` } fn c(x: &mut int) { let c1 = |&mut:| get(x); let c2 = |&mut:| { get(x); set(x); }; //~ ERROR closure requires unique access to `x` } fn d(x: &mut int) { let c1 = |&mut:| set(x); let c2 = |&mut:| set(x); //~ ERROR closure requires unique access to `x` } fn e(x: &mut int) { let c1 = |&mut:| x = panic!(); //~ ERROR closure cannot assign to immutable local variable } fn main() { }