49 lines
1.2 KiB
Rust
49 lines
1.2 KiB
Rust
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// Copyright 2012 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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// Test that we pick which version of `Foo` to run based on whether
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// the type we (ultimately) inferred for `x` is copyable or not.
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//
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// In this case, the two versions are both impls of same trait, and
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// hence we we can resolve method even without knowing yet which
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// version will run (note that the `push` occurs after the call to
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// `foo()`).
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trait Foo {
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fn foo(&self) -> int;
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}
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impl<T:Copy> Foo for Vec<T> {
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fn foo(&self) -> int {1}
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}
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impl<T> Foo for Vec<Box<T>> {
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fn foo(&self) -> int {2}
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}
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fn call_foo_copy() -> int {
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let mut x = Vec::new();
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let y = x.foo();
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x.push(0u);
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y
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}
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fn call_foo_other() -> int {
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let mut x = Vec::new();
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let y = x.foo();
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x.push(box 0i);
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y
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}
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fn main() {
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assert_eq!(call_foo_copy(), 1);
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assert_eq!(call_foo_other(), 2);
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}
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