55 lines
1.3 KiB
Rust
55 lines
1.3 KiB
Rust
// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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use std::ops::Add;
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struct S<T, U = u16> {
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a: T,
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b: U,
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}
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trait Tr {
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fn f(&self) -> Self;
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}
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impl<T: Default + Add<u8, Output = T>, U: Default> Tr for S<T, U> {
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fn f(&self) -> Self {
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let s = Self { a: Default::default(), b: Default::default() };
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match s {
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Self { a, b } => Self { a: a + 1, b: b }
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}
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}
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}
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impl<T: Default, U: Default + Add<u16, Output = U>> S<T, U> {
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fn g(&self) -> Self {
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let s = Self { a: Default::default(), b: Default::default() };
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match s {
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Self { a, b } => Self { a: a, b: b + 1 }
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}
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}
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}
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impl S<u8> {
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fn new() -> Self {
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Self { a: 0, b: 1 }
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}
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}
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fn main() {
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let s0 = S::new();
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let s1 = s0.f();
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assert_eq!(s1.a, 1);
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assert_eq!(s1.b, 0);
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let s2 = s0.g();
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assert_eq!(s2.a, 0);
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assert_eq!(s2.b, 1);
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}
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