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// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
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);
}
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