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58 lines
1.8 KiB
Plaintext
58 lines
1.8 KiB
Plaintext
error[E0782]: expected a type, found a trait
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--> $DIR/ice-unsized-fn-params.rs:13:13
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LL | fn g(b: B) -> B;
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| ^
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= note: `B` it is dyn-incompatible, so it can't be `dyn`
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help: use a new generic type parameter, constrained by `B`
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LL | fn g<T: B>(b: T) -> B;
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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 g(b: impl B) -> B;
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| ++++
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error[E0782]: expected a type, found a trait
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--> $DIR/ice-unsized-fn-params.rs:13:19
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LL | fn g(b: B) -> B;
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| ^
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help: `B` is dyn-incompatible, use `impl B` to return an opaque type, as long as you return a single underlying type
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LL | fn g(b: B) -> impl B;
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| ++++
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error[E0782]: expected a type, found a trait
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--> $DIR/ice-unsized-fn-params.rs:7:13
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LL | fn f(a: A) -> A;
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| ^
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= note: `A` it is dyn-incompatible, so it can't be `dyn`
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help: use a new generic type parameter, constrained by `A`
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LL | fn f<T: A>(a: T) -> A;
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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 f(a: impl A) -> A;
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| ++++
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error[E0782]: expected a type, found a trait
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--> $DIR/ice-unsized-fn-params.rs:7:19
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LL | fn f(a: A) -> A;
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| ^
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help: `A` is dyn-incompatible, use `impl A` to return an opaque type, as long as you return a single underlying type
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LL | fn f(a: A) -> impl A;
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| ++++
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error: aborting due to 4 previous errors
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For more information about this error, try `rustc --explain E0782`.
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