error[E0277]: the trait bound `fn(u32) -> Time {Time}: Resource` is not satisfied --> $DIR/call-on-unimplemented-ctor.rs:3:21 | LL | insert_resource(Time); | --------------- ^^^^ the trait `Resource` is not implemented for fn item `fn(u32) -> Time {Time}` | | | required by a bound introduced by this call | note: required by a bound in `insert_resource` --> $DIR/call-on-unimplemented-ctor.rs:10:23 | LL | fn insert_resource(resource: R) {} | ^^^^^^^^ required by this bound in `insert_resource` help: use parentheses to construct this tuple struct | LL | insert_resource(Time(/* u32 */)); | +++++++++++ error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0277`.