error[E0038]: the trait `Fetcher` cannot be made into an object --> $DIR/undispatchable-receiver-and-wc-references-Self.rs:19:21 | LL | fn get<'a>(self: &'a Box) -> Pin> + 'a>> | ------------- help: consider changing method `get`'s `self` parameter to be `&self`: `&Self` ... LL | fn fetcher() -> Box { | ^^^^^^^^^^^ `Fetcher` cannot be made into an object | note: for a trait to be "dyn-compatible" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit --> $DIR/undispatchable-receiver-and-wc-references-Self.rs:11:22 | LL | pub trait Fetcher: Send + Sync { | ------- this trait cannot be made into an object... LL | fn get<'a>(self: &'a Box) -> Pin> + 'a>> | ^^^^^^^^^^^^^ ...because method `get`'s `self` parameter cannot be dispatched on error[E0038]: the trait `Fetcher` cannot be made into an object --> $DIR/undispatchable-receiver-and-wc-references-Self.rs:25:19 | LL | fn get<'a>(self: &'a Box) -> Pin> + 'a>> | ------------- help: consider changing method `get`'s `self` parameter to be `&self`: `&Self` ... LL | let fetcher = fetcher(); | ^^^^^^^^^ `Fetcher` cannot be made into an object | note: for a trait to be "dyn-compatible" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit --> $DIR/undispatchable-receiver-and-wc-references-Self.rs:11:22 | LL | pub trait Fetcher: Send + Sync { | ------- this trait cannot be made into an object... LL | fn get<'a>(self: &'a Box) -> Pin> + 'a>> | ^^^^^^^^^^^^^ ...because method `get`'s `self` parameter cannot be dispatched on error[E0038]: the trait `Fetcher` cannot be made into an object --> $DIR/undispatchable-receiver-and-wc-references-Self.rs:27:13 | LL | fn get<'a>(self: &'a Box) -> Pin> + 'a>> | ------------- help: consider changing method `get`'s `self` parameter to be `&self`: `&Self` ... LL | let _ = fetcher.get(); | ^^^^^^^^^^^^^ `Fetcher` cannot be made into an object | note: for a trait to be "dyn-compatible" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit --> $DIR/undispatchable-receiver-and-wc-references-Self.rs:11:22 | LL | pub trait Fetcher: Send + Sync { | ------- this trait cannot be made into an object... LL | fn get<'a>(self: &'a Box) -> Pin> + 'a>> | ^^^^^^^^^^^^^ ...because method `get`'s `self` parameter cannot be dispatched on error: aborting due to 3 previous errors For more information about this error, try `rustc --explain E0038`.