// run-pass #![allow(dead_code)] // B and C both require A, so D does as well, twice, but that's just fine trait A { fn a(&self) -> isize; } trait B: A { fn b(&self) -> isize; } trait C: A { fn c(&self) -> isize; } trait D: B + C { fn d(&self) -> isize; } struct S { bogus: () } impl A for S { fn a(&self) -> isize { 10 } } impl B for S { fn b(&self) -> isize { 20 } } impl C for S { fn c(&self) -> isize { 30 } } impl D for S { fn d(&self) -> isize { 40 } } fn f(x: &T) { assert_eq!(x.a(), 10); assert_eq!(x.b(), 20); assert_eq!(x.c(), 30); assert_eq!(x.d(), 40); } pub fn main() { let value = &S { bogus: () }; f(value); }