33 lines
1017 B
Rust
33 lines
1017 B
Rust
#![feature(impl_trait_in_fn_trait_return)]
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use std::fmt::Debug;
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fn fine(x: impl Into<u32>) -> impl Into<u32> { x }
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fn bad_in_ret_position(x: impl Into<u32>) -> impl Into<impl Debug> { x }
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//~^ ERROR nested `impl Trait` is not allowed
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//~| ERROR the trait bound `impl Debug: From<impl Into<u32>>` is not satisfied
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fn bad_in_fn_syntax(x: fn() -> impl Into<impl Debug>) {}
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//~^ ERROR nested `impl Trait` is not allowed
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//~| `impl Trait` only allowed in function and inherent method argument and return types
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fn bad_in_arg_position(_: impl Into<impl Debug>) { }
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//~^ ERROR nested `impl Trait` is not allowed
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struct X;
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impl X {
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fn bad(x: impl Into<u32>) -> impl Into<impl Debug> { x }
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//~^ ERROR nested `impl Trait` is not allowed
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//~| ERROR the trait bound `impl Debug: From<impl Into<u32>>` is not satisfied
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}
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fn allowed_in_assoc_type() -> impl Iterator<Item=impl Fn()> {
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vec![|| println!("woot")].into_iter()
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}
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fn allowed_in_ret_type() -> impl Fn() -> impl Into<u32> {
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|| 5u8
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}
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fn main() {}
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