// 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: F) where F: FnOnce(&isize) { let x = 3; f(&x); } fn main() { let mut x = None; with_int(|y| x = Some(y)); //~^ ERROR cannot infer }