mirror of
https://github.com/rust-lang/rust
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32 lines
628 B
Rust
32 lines
628 B
Rust
//@ check-pass
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//@ edition:2018
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#![feature(ptr_metadata)]
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#![feature(type_alias_impl_trait)]
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mod opaque {
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pub type Opaque = impl std::future::Future;
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fn opaque() -> Opaque {
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async {}
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}
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}
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fn a<T>() {
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// type parameter T is known to be sized
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is_thin::<T>();
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// tail of ADT (which is a type param) is known to be sized
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is_thin::<std::cell::Cell<T>>();
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// opaque type is known to be sized
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is_thin::<opaque::Opaque>();
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}
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fn a2<T: Iterator>() {
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// associated type is known to be sized
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is_thin::<T::Item>();
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}
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fn is_thin<T: std::ptr::Pointee<Metadata = ()>>() {}
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fn main() {}
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