54 lines
1.6 KiB
Rust
54 lines
1.6 KiB
Rust
// 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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/*!
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The kind traits
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Rust types can be classified in various useful ways according to
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intrinsic properties of the type. These classifications, often called
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'kinds', are represented as traits.
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They cannot be implemented by user code, but are instead implemented
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by the compiler automatically for the types to which they apply.
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The 4 kinds are
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* Copy - types that may be copied without allocation. This includes
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scalar types and managed pointers, and exludes owned pointers. It
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also excludes types that implement `Drop`.
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* Owned - owned types and types containing owned types. These types
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may be transferred across task boundaries.
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* Const - types that are deeply immutable. Const types are used for
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freezable data structures.
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`Copy` types include both implicitly copyable types that the compiler
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will copy automatically and non-implicitly copyable types that require
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the `copy` keyword to copy. Types that do not implement `Copy` may
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instead implement `Clone`.
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*/
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#[lang="copy"]
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pub trait Copy {
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// Empty.
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}
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#[lang="owned"]
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pub trait Owned {
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// Empty.
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}
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#[lang="const"]
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pub trait Const {
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// Empty.
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}
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