// 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. fn with_int(f: fn(x: &int)) { let x = 3; f(&x); } fn main() { let mut x: Option<&int> = None; //~ ERROR cannot infer with_int(|y| x = Some(y)); }