error[E0310]: the parameter type `T` may not live long enough --> $DIR/projection-implied-bounds.rs:30:18 | LL | twice(value, |value_ref, item| invoke2(value_ref, item)); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds | help: consider adding an explicit lifetime bound... | LL | fn generic2(value: T) { | +++++++++ error: aborting due to previous error For more information about this error, try `rustc --explain E0310`.