// Copyright 2017 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. // gate-test-universal_impl_trait fn foo(x: impl std::fmt::Debug) { print!("{:?}", x); } //~^ ERROR `impl Trait` in argument position is experimental fn main() {}