1 // Copyright 2017 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
10 #![feature(conservative_impl_trait, universal_impl_trait)]
14 fn fine(x: impl Into<u32>) -> impl Into<u32> { x }
16 fn bad_in_ret_position(x: impl Into<u32>) -> impl Into<impl Debug> { x }
17 //~^ ERROR nested `impl Trait` is not allowed
19 fn bad_in_fn_syntax(x: fn() -> impl Into<impl Debug>) {}
20 //~^ ERROR nested `impl Trait` is not allowed
21 //~^^ `impl Trait` not allowed
23 fn bad_in_arg_position(_: impl Into<impl Debug>) { }
24 //~^ ERROR nested `impl Trait` is not allowed
28 fn bad(x: impl Into<u32>) -> impl Into<impl Debug> { x }
29 //~^ ERROR nested `impl Trait` is not allowed
32 fn allowed_in_assoc_type() -> impl Iterator<Item=impl Fn()> {
33 vec![|| println!("woot")].into_iter()
36 fn allowed_in_ret_type() -> impl Fn() -> impl Into<u32> {
37 //~^ `impl Trait` not allowed