38 lines
1.0 KiB
Rust
38 lines
1.0 KiB
Rust
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// rust-lang/rust#57979 : the initial support for `impl Trait` didn't
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// properly check syntax hidden behind an associated type projection.
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// Here we test behavior of occurrences of `impl Trait` within an
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// `impl Trait` in that context.
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mod allowed {
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#![allow(nested_impl_trait)]
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pub trait Foo<T> { }
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pub trait Bar { }
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pub trait Quux { type Assoc; }
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pub fn demo(_: impl Quux<Assoc=impl Foo<impl Bar>>) { }
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}
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mod warned {
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#![warn(nested_impl_trait)]
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pub trait Foo<T> { }
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pub trait Bar { }
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pub trait Quux { type Assoc; }
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pub fn demo(_: impl Quux<Assoc=impl Foo<impl Bar>>) { }
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//~^ WARN nested `impl Trait` is not allowed
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//~| WARN will become a hard error in a future release!
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}
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mod denied {
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#![deny(nested_impl_trait)]
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pub trait Foo<T> { }
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pub trait Bar { }
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pub trait Quux { type Assoc; }
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pub fn demo(_: impl Quux<Assoc=impl Foo<impl Bar>>) { }
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//~^ ERROR nested `impl Trait` is not allowed
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//~| WARN will become a hard error in a future release!
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}
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fn main() { }
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