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//@ run-pass
#![feature(trait_upcasting)]
trait A {
fn foo_a(&self); //~ WARN method `foo_a` is never used
}
trait B {
fn foo_b(&self);
}
trait C: A + B {
fn foo_c(&self); //~ WARN method `foo_c` is never used
}
struct S(i32);
impl A for S {
fn foo_a(&self) {
unreachable!();
}
}
impl B for S {
fn foo_b(&self) {
assert_eq!(42, self.0);
}
}
impl C for S {
fn foo_c(&self) {
unreachable!();
}
}
fn invoke_inner(b: &dyn B) {
b.foo_b();
}
fn invoke_outer(c: &dyn C) {
invoke_inner(c);
}
fn main() {
let s = S(42);
invoke_outer(&s);
}
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