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513 lines
19 KiB
513 lines
19 KiB
// Copyright 2012-2014 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 Rust Standard Library |
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//! |
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//! The Rust Standard Library is the foundation of portable Rust software, a |
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//! set of minimal and battle-tested shared abstractions for the [broader Rust |
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//! ecosystem][crates.io]. It offers core types, like [`Vec<T>`] and |
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//! [`Option<T>`], library-defined [operations on language |
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//! primitives](#primitives), [standard macros](#macros), [I/O] and |
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//! [multithreading], among [many other things][other]. |
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//! |
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//! `std` is available to all Rust crates by default, just as if each one |
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//! contained an `extern crate std;` import at the [crate root]. Therefore the |
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//! standard library can be accessed in [`use`] statements through the path |
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//! `std`, as in [`use std::env`], or in expressions through the absolute path |
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//! `::std`, as in [`::std::env::args`]. |
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//! |
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//! # How to read this documentation |
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//! |
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//! If you already know the name of what you are looking for, the fastest way to |
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//! find it is to use the <a href="#" onclick="focusSearchBar();">search |
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//! bar</a> at the top of the page. |
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//! |
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//! Otherwise, you may want to jump to one of these useful sections: |
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//! |
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//! * [`std::*` modules](#modules) |
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//! * [Primitive types](#primitives) |
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//! * [Standard macros](#macros) |
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//! * [The Rust Prelude](prelude/index.html) |
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//! |
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//! If this is your first time, the documentation for the standard library is |
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//! written to be casually perused. Clicking on interesting things should |
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//! generally lead you to interesting places. Still, there are important bits |
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//! you don't want to miss, so read on for a tour of the standard library and |
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//! its documentation! |
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//! |
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//! Once you are familiar with the contents of the standard library you may |
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//! begin to find the verbosity of the prose distracting. At this stage in your |
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//! development you may want to press the **[-]** button near the top of the |
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//! page to collapse it into a more skimmable view. |
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//! |
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//! While you are looking at that **[-]** button also notice the **[src]** |
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//! button. Rust's API documentation comes with the source code and you are |
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//! encouraged to read it. The standard library source is generally high |
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//! quality and a peek behind the curtains is often enlightening. |
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//! |
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//! # What is in the standard library documentation? |
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//! |
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//! First of all, The Rust Standard Library is divided into a number of focused |
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//! modules, [all listed further down this page](#modules). These modules are |
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//! the bedrock upon which all of Rust is forged, and they have mighty names |
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//! like [`std::slice`] and [`std::cmp`]. Modules' documentation typically |
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//! includes an overview of the module along with examples, and are a smart |
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//! place to start familiarizing yourself with the library. |
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//! |
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//! Second, implicit methods on [primitive types] are documented here. This can |
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//! be a source of confusion for two reasons: |
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//! |
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//! 1. While primitives are implemented by the compiler, the standard library |
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//! implements methods directly on the primitive types (and it is the only |
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//! library that does so), which are [documented in the section on |
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//! primitives](#primitives). |
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//! 2. The standard library exports many modules *with the same name as |
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//! primitive types*. These define additional items related to the primitive |
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//! type, but not the all-important methods. |
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//! |
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//! So for example there is a [page for the primitive type |
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//! `i32`](primitive.i32.html) that lists all the methods that can be called on |
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//! 32-bit integers (very useful), and there is a [page for the module |
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//! `std::i32`](i32/index.html) that documents the constant values [`MIN`] and |
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//! [`MAX`](i32/constant.MAX.html) (rarely useful). |
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//! |
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//! Note the documentation for the primitives [`str`] and [`[T]`][slice] (also |
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//! called 'slice'). Many method calls on [`String`] and [`Vec<T>`] are actually |
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//! calls to methods on [`str`] and [`[T]`][slice] respectively, via [deref |
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//! coercions][deref-coercions]. |
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//! |
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//! Third, the standard library defines [The Rust Prelude], a small collection |
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//! of items - mostly traits - that are imported into every module of every |
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//! crate. The traits in the prelude are pervasive, making the prelude |
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//! documentation a good entry point to learning about the library. |
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//! |
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//! And finally, the standard library exports a number of standard macros, and |
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//! [lists them on this page](#macros) (technically, not all of the standard |
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//! macros are defined by the standard library - some are defined by the |
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//! compiler - but they are documented here the same). Like the prelude, the |
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//! standard macros are imported by default into all crates. |
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//! |
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//! # Contributing changes to the documentation |
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//! |
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//! Check out the rust contribution guidelines [here]( |
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//! https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md). |
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//! The source for this documentation can be found on [Github](https://github.com/rust-lang). |
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//! To contribute changes, make sure you read the guidelines first, then submit |
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//! pull-requests for your suggested changes. |
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//! |
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//! Contributions are appreciated! If you see a part of the docs that can be |
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//! improved, submit a PR, or chat with us first on irc.mozilla.org #rust-docs. |
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//! |
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//! # A Tour of The Rust Standard Library |
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//! |
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//! The rest of this crate documentation is dedicated to pointing out notable |
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//! features of The Rust Standard Library. |
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//! |
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//! ## Containers and collections |
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//! |
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//! The [`option`] and [`result`] modules define optional and error-handling |
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//! types, [`Option<T>`] and [`Result<T, E>`]. The [`iter`] module defines |
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//! Rust's iterator trait, [`Iterator`], which works with the [`for`] loop to |
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//! access collections. |
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//! |
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//! The standard library exposes three common ways to deal with contiguous |
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//! regions of memory: |
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//! |
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//! * [`Vec<T>`] - A heap-allocated *vector* that is resizable at runtime. |
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//! * [`[T; n]`][array] - An inline *array* with a fixed size at compile time. |
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//! * [`[T]`][slice] - A dynamically sized *slice* into any other kind of contiguous |
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//! storage, whether heap-allocated or not. |
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//! |
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//! Slices can only be handled through some kind of *pointer*, and as such come |
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//! in many flavors such as: |
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//! |
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//! * `&[T]` - *shared slice* |
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//! * `&mut [T]` - *mutable slice* |
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//! * [`Box<[T]>`][owned slice] - *owned slice* |
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//! |
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//! [`str`], a UTF-8 string slice, is a primitive type, and the standard library |
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//! defines many methods for it. Rust [`str`]s are typically accessed as |
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//! immutable references: `&str`. Use the owned [`String`] for building and |
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//! mutating strings. |
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//! |
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//! For converting to strings use the [`format!`] macro, and for converting from |
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//! strings use the [`FromStr`] trait. |
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//! |
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//! Data may be shared by placing it in a reference-counted box or the [`Rc`] |
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//! type, and if further contained in a [`Cell`] or [`RefCell`], may be mutated |
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//! as well as shared. Likewise, in a concurrent setting it is common to pair an |
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//! atomically-reference-counted box, [`Arc`], with a [`Mutex`] to get the same |
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//! effect. |
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//! |
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//! The [`collections`] module defines maps, sets, linked lists and other |
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//! typical collection types, including the common [`HashMap<K, V>`]. |
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//! |
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//! ## Platform abstractions and I/O |
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//! |
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//! Besides basic data types, the standard library is largely concerned with |
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//! abstracting over differences in common platforms, most notably Windows and |
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//! Unix derivatives. |
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//! |
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//! Common types of I/O, including [files], [TCP], [UDP], are defined in the |
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//! [`io`], [`fs`], and [`net`] modules. |
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//! |
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//! The [`thread`] module contains Rust's threading abstractions. [`sync`] |
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//! contains further primitive shared memory types, including [`atomic`] and |
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//! [`mpsc`], which contains the channel types for message passing. |
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//! |
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//! [I/O]: io/index.html |
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//! [`MIN`]: i32/constant.MIN.html |
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//! [TCP]: net/struct.TcpStream.html |
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//! [The Rust Prelude]: prelude/index.html |
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//! [UDP]: net/struct.UdpSocket.html |
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//! [`::std::env::args`]: env/fn.args.html |
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//! [`Arc`]: sync/struct.Arc.html |
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//! [owned slice]: boxed/index.html |
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//! [`Cell`]: cell/struct.Cell.html |
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//! [`FromStr`]: str/trait.FromStr.html |
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//! [`HashMap<K, V>`]: collections/struct.HashMap.html |
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//! [`Iterator`]: iter/trait.Iterator.html |
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//! [`Mutex`]: sync/struct.Mutex.html |
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//! [`Option<T>`]: option/enum.Option.html |
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//! [`Rc`]: rc/index.html |
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//! [`RefCell`]: cell/struct.RefCell.html |
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//! [`Result<T, E>`]: result/enum.Result.html |
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//! [`String`]: string/struct.String.html |
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//! [`Vec<T>`]: vec/index.html |
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//! [array]: primitive.array.html |
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//! [slice]: primitive.slice.html |
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//! [`atomic`]: sync/atomic/index.html |
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//! [`collections`]: collections/index.html |
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//! [`for`]: ../book/first-edition/loops.html#for |
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//! [`format!`]: macro.format.html |
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//! [`fs`]: fs/index.html |
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//! [`io`]: io/index.html |
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//! [`iter`]: iter/index.html |
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//! [`mpsc`]: sync/mpsc/index.html |
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//! [`net`]: net/index.html |
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//! [`option`]: option/index.html |
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//! [`result`]: result/index.html |
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//! [`std::cmp`]: cmp/index.html |
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//! [`std::slice`]: slice/index.html |
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//! [`str`]: primitive.str.html |
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//! [`sync`]: sync/index.html |
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//! [`thread`]: thread/index.html |
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//! [`use std::env`]: env/index.html |
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//! [`use`]: ../book/first-edition/crates-and-modules.html#importing-modules-with-use |
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//! [crate root]: ../book/first-edition/crates-and-modules.html#basic-terminology-crates-and-modules |
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//! [crates.io]: https://crates.io |
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//! [deref-coercions]: ../book/second-edition/ch15-02-deref.html#implicit-deref-coercions-with-functions-and-methods |
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//! [files]: fs/struct.File.html |
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//! [multithreading]: thread/index.html |
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//! [other]: #what-is-in-the-standard-library-documentation |
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//! [primitive types]: ../book/first-edition/primitive-types.html |
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#![stable(feature = "rust1", since = "1.0.0")] |
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#![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png", |
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html_favicon_url = "https://doc.rust-lang.org/favicon.ico", |
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html_root_url = "https://doc.rust-lang.org/nightly/", |
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html_playground_url = "https://play.rust-lang.org/", |
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issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/", |
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test(no_crate_inject, attr(deny(warnings))), |
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test(attr(allow(dead_code, deprecated, unused_variables, unused_mut))))] |
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// Don't link to std. We are std. |
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#![no_std] |
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//#![deny(missing_docs)] |
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#![deny(missing_debug_implementations)] |
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// Tell the compiler to link to either panic_abort or panic_unwind |
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#![needs_panic_runtime] |
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// Turn warnings into errors, but only after stage0, where it can be useful for |
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// code to emit warnings during language transitions |
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//#![cfg_attr(not(stage0), deny(warnings))] |
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// std may use features in a platform-specific way |
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#![allow(unused_features)] |
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// std is implemented with unstable features, many of which are internal |
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// compiler details that will never be stable |
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#![feature(alloc)] |
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#![feature(allocator_api)] |
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#![feature(alloc_system)] |
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#![feature(allocator_internals)] |
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#![feature(allow_internal_unsafe)] |
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#![feature(allow_internal_unstable)] |
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#![feature(align_offset)] |
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#![feature(array_error_internals)] |
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#![feature(ascii_ctype)] |
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#![feature(asm)] |
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#![feature(attr_literals)] |
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#![feature(box_syntax)] |
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#![feature(cfg_target_has_atomic)] |
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#![feature(cfg_target_thread_local)] |
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#![feature(cfg_target_vendor)] |
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#![feature(char_error_internals)] |
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#![feature(char_internals)] |
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#![feature(collections_range)] |
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#![feature(compiler_builtins_lib)] |
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#![feature(const_fn)] |
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#![feature(core_float)] |
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#![feature(core_intrinsics)] |
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#![feature(dropck_eyepatch)] |
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#![feature(exact_size_is_empty)] |
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#![feature(fs_read_write)] |
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#![feature(fixed_size_array)] |
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#![feature(float_from_str_radix)] |
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#![feature(fn_traits)] |
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#![feature(fnbox)] |
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#![feature(fused)] |
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#![feature(generic_param_attrs)] |
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#![feature(hashmap_hasher)] |
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#![feature(heap_api)] |
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#![feature(i128)] |
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#![feature(i128_type)] |
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#![feature(inclusive_range)] |
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#![feature(int_error_internals)] |
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#![feature(integer_atomics)] |
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#![feature(into_cow)] |
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#![feature(lang_items)] |
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#![feature(libc)] |
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#![feature(link_args)] |
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#![feature(linkage)] |
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#![feature(macro_reexport)] |
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#![feature(macro_vis_matcher)] |
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#![feature(needs_panic_runtime)] |
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#![feature(never_type)] |
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#![feature(num_bits_bytes)] |
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#![feature(old_wrapping)] |
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#![feature(on_unimplemented)] |
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#![feature(oom)] |
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#![feature(optin_builtin_traits)] |
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#![feature(panic_unwind)] |
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#![feature(peek)] |
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#![feature(placement_in_syntax)] |
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#![feature(placement_new_protocol)] |
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#![feature(prelude_import)] |
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#![feature(ptr_internals)] |
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#![feature(rand)] |
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#![feature(raw)] |
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#![feature(rustc_attrs)] |
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#![feature(sip_hash_13)] |
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#![feature(slice_bytes)] |
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#![feature(slice_concat_ext)] |
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#![feature(slice_internals)] |
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#![feature(slice_patterns)] |
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#![feature(staged_api)] |
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#![feature(stmt_expr_attributes)] |
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#![feature(str_char)] |
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#![feature(str_internals)] |
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#![feature(str_utf16)] |
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#![feature(termination_trait)] |
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#![feature(test, rustc_private)] |
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#![feature(thread_local)] |
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#![feature(toowned_clone_into)] |
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#![feature(try_from)] |
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#![feature(unboxed_closures)] |
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#![feature(unicode)] |
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#![feature(untagged_unions)] |
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#![feature(unwind_attributes)] |
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#![feature(vec_push_all)] |
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#![feature(doc_cfg)] |
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#![feature(doc_masked)] |
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#![feature(doc_spotlight)] |
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#![cfg_attr(test, feature(update_panic_count))] |
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#![cfg_attr(windows, feature(used))] |
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#![default_lib_allocator] |
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// Always use alloc_system during stage0 since we don't know if the alloc_* |
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// crate the stage0 compiler will pick by default is enabled (e.g. |
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// if the user has disabled jemalloc in `./configure`). |
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// `force_alloc_system` is *only* intended as a workaround for local rebuilds |
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// with a rustc without jemalloc. |
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// FIXME(#44236) shouldn't need MSVC logic |
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#![cfg_attr(all(not(target_env = "msvc"), |
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any(stage0, feature = "force_alloc_system")), |
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feature(global_allocator))] |
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#[cfg(all(not(target_env = "msvc"), |
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any(stage0, feature = "force_alloc_system")))] |
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#[global_allocator] |
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static ALLOC: alloc_system::System = alloc_system::System; |
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// Explicitly import the prelude. The compiler uses this same unstable attribute |
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// to import the prelude implicitly when building crates that depend on std. |
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#[prelude_import] |
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#[allow(unused)] |
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use prelude::v1::*; |
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// Access to Bencher, etc. |
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#[cfg(test)] extern crate test; |
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#[cfg(test)] extern crate rand; |
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// We want to re-export a few macros from core but libcore has already been |
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// imported by the compiler (via our #[no_std] attribute) In this case we just |
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// add a new crate name so we can attach the re-exports to it. |
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#[macro_reexport(assert, assert_eq, assert_ne, debug_assert, debug_assert_eq, |
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debug_assert_ne, unreachable, unimplemented, write, writeln, try)] |
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extern crate core as __core; |
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#[macro_use] |
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#[macro_reexport(vec, format)] |
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extern crate alloc; |
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extern crate alloc_system; |
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extern crate std_unicode; |
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#[doc(masked)] |
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extern crate libc; |
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// 3DS-specific dependency |
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extern crate ctru_sys as libctru; |
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// We always need an unwinder currently for backtraces |
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#[doc(masked)] |
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#[allow(unused_extern_crates)] |
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extern crate unwind; |
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// compiler-rt intrinsics |
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#[doc(masked)] |
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extern crate compiler_builtins; |
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// During testing, this crate is not actually the "real" std library, but rather |
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// it links to the real std library, which was compiled from this same source |
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// code. So any lang items std defines are conditionally excluded (or else they |
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// wolud generate duplicate lang item errors), and any globals it defines are |
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// _not_ the globals used by "real" std. So this import, defined only during |
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// testing gives test-std access to real-std lang items and globals. See #2912 |
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#[cfg(test)] extern crate std as realstd; |
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|
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// The standard macros that are not built-in to the compiler. |
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#[macro_use] |
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mod macros; |
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// The Rust prelude |
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pub mod prelude; |
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// Public module declarations and re-exports |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::any; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::cell; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::clone; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::cmp; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::convert; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::default; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::hash; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::intrinsics; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::iter; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::marker; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::mem; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::ops; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::ptr; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::raw; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::result; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::option; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::isize; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::i8; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::i16; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::i32; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::i64; |
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#[unstable(feature = "i128", issue = "35118")] |
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pub use core::i128; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::usize; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::u8; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::u16; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::u32; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use core::u64; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use alloc::boxed; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use alloc::rc; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use alloc::borrow; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use alloc::fmt; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use alloc::slice; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use alloc::str; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use alloc::string; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use alloc::vec; |
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#[stable(feature = "rust1", since = "1.0.0")] |
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pub use std_unicode::char; |
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#[unstable(feature = "i128", issue = "35118")] |
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pub use core::u128; |
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pub mod f32; |
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pub mod f64; |
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#[macro_use] |
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pub mod thread; |
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pub mod ascii; |
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pub mod collections; |
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pub mod env; |
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pub mod error; |
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pub mod ffi; |
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pub mod fs; |
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pub mod io; |
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pub mod net; |
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pub mod num; |
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pub mod os; |
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pub mod panic; |
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pub mod path; |
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pub mod process; |
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pub mod sync; |
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pub mod time; |
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pub mod heap; |
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// Platform-abstraction modules |
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#[macro_use] |
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mod sys_common; |
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mod sys; |
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// Private support modules |
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mod panicking; |
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mod memchr; |
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// The runtime entry point and a few unstable public functions used by the |
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// compiler |
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pub mod rt; |
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// The trait to support returning arbitrary types in the main function |
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mod termination; |
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#[unstable(feature = "termination_trait", issue = "43301")] |
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pub use self::termination::Termination; |
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// Include a number of private modules that exist solely to provide |
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// the rustdoc documentation for primitive types. Using `include!` |
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// because rustdoc only looks for these modules at the crate level. |
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include!("primitive_docs.rs");
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