updated rtic_bare7

examples/rtic_bare7.rs

@@ -231,6 +231,10 @@ fn _toggleable_generic<E>(led: &mut dyn ToggleableOutputPin<Error = E>) {
 //    way to implement it more efficiently. Remember, zero-cost is not without cost
 //    just that it is as good as it possibly gets (you can't make it better by hand).
 //
+//    (You can also force the compiler to deduce the type at compile time, by using
+//    `impl` instead of `dyn`, if you are sure you don't want the compiler to
+//    "fallback" to dynamic dispatch.)
+//
 //    You might find Rust to have long compile times. Yes you are right,
 //    and this type of deep analysis done in release mode is part of the story.
 //    On the other hand, the aggressive optimization allows us to code