traitFoo<A>{fnfoo(&self,a: A)-> A{a}}traitNotRelevant<A>{fnnr(&self,a: A)-> A{a}}structBar;implFoo<i32>forBar{}implFoo<u8>forBar{}implNotRelevant<usize>forBar{}fnmain(){letf1=Bar;f1.foo(1usize);//~^ error: the trait bound `Bar: Foo<usize>` is not satisfied}