// Copyright 2018 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. // If the unstable API is the only possible solution, // still emit E0658 "use of unstable library feature". // aux-build:inference_unstable_iterator.rs extern crate inference_unstable_iterator; use inference_unstable_iterator::IpuIterator; fn main() { assert_eq!('x'.ipu_flatten(), 0); //~ ERROR E0658 }