34 lines
859 B
Rust
34 lines
859 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 MapLookup<Q> {
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type MapValue;
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}
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impl<K> MapLookup<K> for K {
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type MapValue = K;
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}
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trait Map: MapLookup<<Self as Map>::Key> {
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type Key;
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}
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impl<K> Map for K {
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type Key = K;
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}
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fn main() {
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let _ = &()
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as &Map<Key=u32,MapValue=u32>;
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//~^ ERROR the trait `Map` cannot be made into an object
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//~| NOTE the trait cannot use `Self` as a type parameter
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}
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