34 lines
800 B
Rust
34 lines
800 B
Rust
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// Copyright 2015 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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trait Foo {
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fn mk() -> Self;
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}
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impl<T: Default> Foo for T {
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default fn mk() -> T {
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T::default()
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}
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}
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impl Foo for Vec<u8> {
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fn mk() -> Vec<u8> {
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vec![0]
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}
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}
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fn main() {
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let v1: Vec<i32> = Foo::mk();
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let v2: Vec<u8> = Foo::mk();
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assert!(v1.len() == 0);
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assert!(v2.len() == 1);
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}
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