mirror of https://github.com/rust-lang/rust
23 lines
506 B
Rust
23 lines
506 B
Rust
// Test that `dyn ?Sized` (i.e., a trait object with only a maybe buond) is not allowed, when just
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// `?Sized` results from trait alias expansion.
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#![feature(trait_alias)]
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trait S = ?Sized;
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// Nest a couple of levels deep:
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trait _0 = S;
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trait _1 = _0;
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// Straight list expansion:
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type _T0 = dyn _1;
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//~^ ERROR at least one trait is required for an object type [E0224]
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// Twice:
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trait _2 = _1 + _1;
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type _T1 = dyn _2;
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//~^ ERROR at least one trait is required for an object type [E0224]
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fn main() {}
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