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22 lines
903 B
Plaintext
22 lines
903 B
Plaintext
error[E0746]: return type cannot have an unboxed trait object
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--> $DIR/box-instead-of-dyn-fn.rs:5:56
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LL | fn print_on_or_the_other<'a>(a: i32, b: &'a String) -> dyn Fn() + 'a {
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| ^^^^^^^^^^^^^ doesn't have a size known at compile-time
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help: return an `impl Trait` instead of a `dyn Trait`, if all returned values are the same type
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LL | fn print_on_or_the_other<'a>(a: i32, b: &'a String) -> impl Fn() + 'a {
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| ~~~~
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help: box the return type, and wrap all of the returned values in `Box::new`
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LL ~ fn print_on_or_the_other<'a>(a: i32, b: &'a String) -> Box<dyn Fn() + 'a> {
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LL |
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LL | if a % 2 == 0 {
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LL ~ Box::new(move || println!("{a}"))
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error: aborting due to 1 previous error
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For more information about this error, try `rustc --explain E0746`.
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