mirror of
https://github.com/rust-lang/rust.git
synced 2024-12-11 08:05:12 +00:00
33 lines
1004 B
Rust
33 lines
1004 B
Rust
#![feature(impl_trait_in_fn_trait_return)]
|
|
use std::fmt::Debug;
|
|
|
|
fn fine(x: impl Into<u32>) -> impl Into<u32> { x }
|
|
|
|
fn bad_in_ret_position(x: impl Into<u32>) -> impl Into<impl Debug> { x }
|
|
//~^ ERROR nested `impl Trait` is not allowed
|
|
//~| ERROR the trait bound `impl Debug: From<impl Into<u32>>` is not satisfied
|
|
|
|
fn bad_in_fn_syntax(x: fn() -> impl Into<impl Debug>) {}
|
|
//~^ ERROR nested `impl Trait` is not allowed
|
|
//~| `impl Trait` only allowed in function and inherent method return types
|
|
|
|
fn bad_in_arg_position(_: impl Into<impl Debug>) { }
|
|
//~^ ERROR nested `impl Trait` is not allowed
|
|
|
|
struct X;
|
|
impl X {
|
|
fn bad(x: impl Into<u32>) -> impl Into<impl Debug> { x }
|
|
//~^ ERROR nested `impl Trait` is not allowed
|
|
//~| ERROR the trait bound `impl Debug: From<impl Into<u32>>` is not satisfied
|
|
}
|
|
|
|
fn allowed_in_assoc_type() -> impl Iterator<Item=impl Fn()> {
|
|
vec![|| println!("woot")].into_iter()
|
|
}
|
|
|
|
fn allowed_in_ret_type() -> impl Fn() -> impl Into<u32> {
|
|
|| 5u8
|
|
}
|
|
|
|
fn main() {}
|