mirror of https://github.com/rust-lang/rust
37 lines
1.0 KiB
Rust
37 lines
1.0 KiB
Rust
// Test related to when a region bound is required to be specified.
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trait IsStatic : 'static { }
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trait IsSend : Send { }
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trait Is<'a> : 'a { }
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trait Is2<'a> : 'a { }
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trait SomeTrait { }
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// Bounds on object types:
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struct Foo<'a,'b,'c> { //~ ERROR parameter `'c` is never used
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// All of these are ok, because we can derive exactly one bound:
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a: Box<dyn IsStatic>,
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b: Box<dyn Is<'static>>,
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c: Box<dyn Is<'a>>,
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d: Box<dyn IsSend>,
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e: Box<dyn Is<'a>+Send>, // we can derive two bounds, but one is 'static, so ok
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f: Box<dyn SomeTrait>, // OK, defaults to 'static due to RFC 599.
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g: Box<dyn SomeTrait+'a>,
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z: Box<dyn Is<'a>+'b+'c>,
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//~^ ERROR only a single explicit lifetime bound is permitted
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//~| ERROR lifetime bound not satisfied
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}
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fn test<
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'a,
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'b,
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A:IsStatic,
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B:Is<'a>+Is2<'b>, // OK in a parameter, but not an object type.
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C:'b+Is<'a>+Is2<'b>,
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D:Is<'a>+Is2<'static>,
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E:'a+'b // OK in a parameter, but not an object type.
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>() { }
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fn main() { }
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