mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-27 01:04:03 +00:00
46 lines
874 B
Rust
46 lines
874 B
Rust
//@ run-pass
|
|
use std::ops::Add;
|
|
|
|
struct S<T, U = u16> {
|
|
a: T,
|
|
b: U,
|
|
}
|
|
|
|
trait Tr {
|
|
fn f(&self) -> Self;
|
|
}
|
|
|
|
impl<T: Default + Add<u8, Output = T>, U: Default> Tr for S<T, U> {
|
|
fn f(&self) -> Self {
|
|
let s = Self { a: Default::default(), b: Default::default() };
|
|
match s {
|
|
Self { a, b } => Self { a: a + 1, b: b }
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<T: Default, U: Default + Add<u16, Output = U>> S<T, U> {
|
|
fn g(&self) -> Self {
|
|
let s = Self { a: Default::default(), b: Default::default() };
|
|
match s {
|
|
Self { a, b } => Self { a: a, b: b + 1 }
|
|
}
|
|
}
|
|
}
|
|
|
|
impl S<u8> {
|
|
fn new() -> Self {
|
|
Self { a: 0, b: 1 }
|
|
}
|
|
}
|
|
|
|
fn main() {
|
|
let s0 = S::new();
|
|
let s1 = s0.f();
|
|
assert_eq!(s1.a, 1);
|
|
assert_eq!(s1.b, 0);
|
|
let s2 = s0.g();
|
|
assert_eq!(s2.a, 0);
|
|
assert_eq!(s2.b, 1);
|
|
}
|