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45 lines
1.6 KiB
Plaintext
45 lines
1.6 KiB
Plaintext
error[E0782]: expected a type, found a trait
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--> $DIR/dyn-2021-edition-error.rs:3:17
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LL | fn function(x: &SomeTrait, y: Box<SomeTrait>) {
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| ^^^^^^^^^
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help: use a new generic type parameter, constrained by `SomeTrait`
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LL | fn function<T: SomeTrait>(x: &T, y: Box<SomeTrait>) {
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| ++++++++++++++ ~
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help: you can also use an opaque type, but users won't be able to specify the type parameter when calling the `fn`, having to rely exclusively on type inference
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LL | fn function(x: &impl SomeTrait, y: Box<SomeTrait>) {
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| ++++
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help: alternatively, use a trait object to accept any type that implements `SomeTrait`, accessing its methods at runtime using dynamic dispatch
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LL | fn function(x: &dyn SomeTrait, y: Box<SomeTrait>) {
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| +++
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error[E0782]: expected a type, found a trait
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--> $DIR/dyn-2021-edition-error.rs:3:35
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LL | fn function(x: &SomeTrait, y: Box<SomeTrait>) {
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| ^^^^^^^^^
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help: you can add the `dyn` keyword if you want a trait object
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LL | fn function(x: &SomeTrait, y: Box<dyn SomeTrait>) {
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| +++
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error[E0782]: expected a type, found a trait
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--> $DIR/dyn-2021-edition-error.rs:6:14
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LL | let _x: &SomeTrait = todo!();
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| ^^^^^^^^^
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help: you can add the `dyn` keyword if you want a trait object
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LL | let _x: &dyn SomeTrait = todo!();
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| +++
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error: aborting due to 3 previous errors
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For more information about this error, try `rustc --explain E0782`.
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