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42 lines
1.9 KiB
Plaintext
42 lines
1.9 KiB
Plaintext
error[E0038]: the trait `Trait` cannot be made into an object
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--> $DIR/object-unsafe-trait-should-use-where-sized.rs:9:12
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LL | fn bar(x: &dyn Trait) {}
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| ^^^^^^^^^ `Trait` cannot be made into an object
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note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
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--> $DIR/object-unsafe-trait-should-use-where-sized.rs:5:8
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LL | trait Trait {
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| ----- this trait cannot be made into an object...
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LL | fn foo() where Self: Other, { }
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| ^^^ ...because associated function `foo` has no `self` parameter
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LL | fn bar(self: ()) {}
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| ^^ ...because method `bar`'s `self` parameter cannot be dispatched on
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help: consider turning `foo` into a method by giving it a `&self` argument
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LL | fn foo(&self) where Self: Other, { }
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| +++++
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help: alternatively, consider constraining `foo` so it does not apply to trait objects
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LL | fn foo() where Self: Other, Self: Sized { }
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| ~~~~~~~~~~~~~
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help: consider changing method `bar`'s `self` parameter to be `&self`
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LL | fn bar(self: &Self) {}
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| ~~~~~
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error[E0307]: invalid `self` parameter type: `()`
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--> $DIR/object-unsafe-trait-should-use-where-sized.rs:6:18
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LL | fn bar(self: ()) {}
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| ^^
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= note: type of `self` must be `Self` or a type that dereferences to it
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= help: consider changing to `self`, `&self`, `&mut self`, `self: Box<Self>`, `self: Rc<Self>`, `self: Arc<Self>`, or `self: Pin<P>` (where P is one of the previous types except `Self`)
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error: aborting due to 2 previous errors
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Some errors have detailed explanations: E0038, E0307.
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For more information about an error, try `rustc --explain E0038`.
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