std: Deny most warnings in doctests
Allow a few specific ones but otherwise this helps ensure that our examples are squeaky clean! Closes #18199
This commit is contained in:
parent
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18 changed files with 202 additions and 215 deletions
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@ -229,7 +229,6 @@ macro_rules! writeln {
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/// Iterators:
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///
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/// ```
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/// # #![feature(core)]
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/// fn divide_by_three(x: u32) -> u32 { // one of the poorest implementations of x/3
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/// for i in 0.. {
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/// if 3*i < i { panic!("u32 overflow"); }
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@ -304,7 +304,6 @@ impl<T, S> HashSet<T, S>
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/// # Examples
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///
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/// ```
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/// # #![feature(core)]
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/// use std::collections::HashSet;
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/// let a: HashSet<_> = [1, 2, 3].iter().cloned().collect();
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/// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect();
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@ -335,7 +334,6 @@ impl<T, S> HashSet<T, S>
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/// # Examples
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///
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/// ```
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/// # #![feature(core)]
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/// use std::collections::HashSet;
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/// let a: HashSet<_> = [1, 2, 3].iter().cloned().collect();
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/// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect();
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@ -362,7 +360,6 @@ impl<T, S> HashSet<T, S>
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/// # Examples
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///
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/// ```
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/// # #![feature(core)]
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/// use std::collections::HashSet;
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/// let a: HashSet<_> = [1, 2, 3].iter().cloned().collect();
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/// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect();
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@ -388,7 +385,6 @@ impl<T, S> HashSet<T, S>
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/// # Examples
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///
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/// ```
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/// # #![feature(core)]
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/// use std::collections::HashSet;
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/// let a: HashSet<_> = [1, 2, 3].iter().cloned().collect();
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/// let b: HashSet<_> = [4, 2, 3, 4].iter().cloned().collect();
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@ -471,7 +467,6 @@ impl<T, S> HashSet<T, S>
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/// # Examples
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///
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/// ```
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/// # #![feature(core)]
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/// use std::collections::HashSet;
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///
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/// let set: HashSet<_> = [1, 2, 3].iter().cloned().collect();
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@ -491,7 +486,6 @@ impl<T, S> HashSet<T, S>
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/// # Examples
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///
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/// ```
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/// # #![feature(core)]
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/// use std::collections::HashSet;
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///
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/// let a: HashSet<_> = [1, 2, 3].iter().cloned().collect();
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@ -513,7 +507,6 @@ impl<T, S> HashSet<T, S>
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/// # Examples
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///
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/// ```
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/// # #![feature(core)]
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/// use std::collections::HashSet;
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///
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/// let sup: HashSet<_> = [1, 2, 3].iter().cloned().collect();
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@ -535,7 +528,6 @@ impl<T, S> HashSet<T, S>
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/// # Examples
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///
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/// ```
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/// # #![feature(core)]
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/// use std::collections::HashSet;
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///
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/// let sub: HashSet<_> = [1, 2].iter().cloned().collect();
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@ -10,16 +10,18 @@
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//! Collection types.
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//!
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//! Rust's standard collection library provides efficient implementations of the most common
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//! general purpose programming data structures. By using the standard implementations,
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//! it should be possible for two libraries to communicate without significant data conversion.
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//! Rust's standard collection library provides efficient implementations of the
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//! most common general purpose programming data structures. By using the
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//! standard implementations, it should be possible for two libraries to
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//! communicate without significant data conversion.
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//!
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//! To get this out of the way: you should probably just use `Vec` or `HashMap`. These two
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//! collections cover most use cases for generic data storage and processing. They are
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//! exceptionally good at doing what they do. All the other collections in the standard
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//! library have specific use cases where they are the optimal choice, but these cases are
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//! borderline *niche* in comparison. Even when `Vec` and `HashMap` are technically suboptimal,
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//! they're probably a good enough choice to get started.
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//! To get this out of the way: you should probably just use `Vec` or `HashMap`.
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//! These two collections cover most use cases for generic data storage and
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//! processing. They are exceptionally good at doing what they do. All the other
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//! collections in the standard library have specific use cases where they are
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//! the optimal choice, but these cases are borderline *niche* in comparison.
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//! Even when `Vec` and `HashMap` are technically suboptimal, they're probably a
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//! good enough choice to get started.
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//!
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//! Rust's collections can be grouped into four major categories:
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//!
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//!
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//! # When Should You Use Which Collection?
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//!
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//! These are fairly high-level and quick break-downs of when each collection should be
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//! considered. Detailed discussions of strengths and weaknesses of individual collections
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//! can be found on their own documentation pages.
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//! These are fairly high-level and quick break-downs of when each collection
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//! should be considered. Detailed discussions of strengths and weaknesses of
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//! individual collections can be found on their own documentation pages.
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//!
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//! ### Use a `Vec` when:
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//! * You want to collect items up to be processed or sent elsewhere later, and don't care about
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//! any properties of the actual values being stored.
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//! * You want a sequence of elements in a particular order, and will only be appending to
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//! (or near) the end.
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//! * You want to collect items up to be processed or sent elsewhere later, and
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//! don't care about any properties of the actual values being stored.
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//! * You want a sequence of elements in a particular order, and will only be
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//! appending to (or near) the end.
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//! * You want a stack.
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//! * You want a resizable array.
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//! * You want a heap-allocated array.
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//!
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//! ### Use a `VecDeque` when:
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//! * You want a `Vec` that supports efficient insertion at both ends of the sequence.
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//! * You want a `Vec` that supports efficient insertion at both ends of the
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//! sequence.
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//! * You want a queue.
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//! * You want a double-ended queue (deque).
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//!
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//! ### Use a `LinkedList` when:
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//! * You want a `Vec` or `VecDeque` of unknown size, and can't tolerate amortization.
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//! * You want a `Vec` or `VecDeque` of unknown size, and can't tolerate
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//! amortization.
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//! * You want to efficiently split and append lists.
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//! * You are *absolutely* certain you *really*, *truly*, want a doubly linked list.
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//! * You are *absolutely* certain you *really*, *truly*, want a doubly linked
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//! list.
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//!
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//! ### Use a `HashMap` when:
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//! * You want to associate arbitrary keys with an arbitrary value.
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//!
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//! ### Use a `BTreeMap` when:
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//! * You're interested in what the smallest or largest key-value pair is.
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//! * You want to find the largest or smallest key that is smaller or larger than something
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//! * You want to find the largest or smallest key that is smaller or larger
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//! than something
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//! * You want to be able to get all of the entries in order on-demand.
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//! * You want a sorted map.
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//!
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//! * You want a `BitVec`, but want `Set` properties
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//!
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//! ### Use a `BinaryHeap` when:
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//! * You want to store a bunch of elements, but only ever want to process the "biggest"
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//! or "most important" one at any given time.
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//!
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//! * You want to store a bunch of elements, but only ever want to process the
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//! "biggest" or "most important" one at any given time.
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//! * You want a priority queue.
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//!
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//! # Performance
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//!
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//! Choosing the right collection for the job requires an understanding of what each collection
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//! is good at. Here we briefly summarize the performance of different collections for certain
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//! important operations. For further details, see each type's documentation, and note that the
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//! names of actual methods may differ from the tables below on certain collections.
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//! Choosing the right collection for the job requires an understanding of what
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//! each collection is good at. Here we briefly summarize the performance of
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//! different collections for certain important operations. For further details,
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//! see each type's documentation, and note that the names of actual methods may
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//! differ from the tables below on certain collections.
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//!
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//! Throughout the documentation, we will follow a few conventions. For all operations,
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//! the collection's size is denoted by n. If another collection is involved in the operation, it
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//! contains m elements. Operations which have an *amortized* cost are suffixed with a `*`.
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//! Operations with an *expected* cost are suffixed with a `~`.
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//! Throughout the documentation, we will follow a few conventions. For all
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//! operations, the collection's size is denoted by n. If another collection is
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//! involved in the operation, it contains m elements. Operations which have an
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//! *amortized* cost are suffixed with a `*`. Operations with an *expected*
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//! cost are suffixed with a `~`.
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//!
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//! All amortized costs are for the potential need to resize when capacity is exhausted.
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//! If a resize occurs it will take O(n) time. Our collections never automatically shrink,
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//! so removal operations aren't amortized. Over a sufficiently large series of
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//! operations, the average cost per operation will deterministically equal the given cost.
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//! All amortized costs are for the potential need to resize when capacity is
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//! exhausted. If a resize occurs it will take O(n) time. Our collections never
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//! automatically shrink, so removal operations aren't amortized. Over a
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//! sufficiently large series of operations, the average cost per operation will
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//! deterministically equal the given cost.
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//!
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//! Only HashMap has expected costs, due to the probabilistic nature of hashing. It is
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//! theoretically possible, though very unlikely, for HashMap to experience worse performance.
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//! Only HashMap has expected costs, due to the probabilistic nature of hashing.
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//! It is theoretically possible, though very unlikely, for HashMap to
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//! experience worse performance.
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//!
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//! ## Sequences
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//!
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//!
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//! ## Maps
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//!
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//! For Sets, all operations have the cost of the equivalent Map operation. For BitSet,
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//! For Sets, all operations have the cost of the equivalent Map operation. For
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//! BitSet,
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//! refer to VecMap.
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//!
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//! | | get | insert | remove | predecessor |
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//! | BTreeMap | O(log n) | O(log n) | O(log n) | O(log n) |
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//! | VecMap | O(1) | O(1)? | O(1) | O(n) |
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//!
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//! Note that VecMap is *incredibly* inefficient in terms of space. The O(1) insertion time
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//! assumes space for the element is already allocated. Otherwise, a large key may require a
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//! massive reallocation, with no direct relation to the number of elements in the collection.
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//! VecMap should only be seriously considered for small keys.
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//! Note that VecMap is *incredibly* inefficient in terms of space. The O(1)
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//! insertion time assumes space for the element is already allocated.
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//! Otherwise, a large key may require a massive reallocation, with no direct
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//! relation to the number of elements in the collection. VecMap should only be
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//! seriously considered for small keys.
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//!
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//! Note also that BTreeMap's precise preformance depends on the value of B.
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//!
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//! # Correct and Efficient Usage of Collections
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//!
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//! Of course, knowing which collection is the right one for the job doesn't instantly
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//! permit you to use it correctly. Here are some quick tips for efficient and correct
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//! usage of the standard collections in general. If you're interested in how to use a
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//! specific collection in particular, consult its documentation for detailed discussion
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//! and code examples.
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//! Of course, knowing which collection is the right one for the job doesn't
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//! instantly permit you to use it correctly. Here are some quick tips for
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//! efficient and correct usage of the standard collections in general. If
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//! you're interested in how to use a specific collection in particular, consult
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//! its documentation for detailed discussion and code examples.
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//!
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//! ## Capacity Management
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//!
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//! Many collections provide several constructors and methods that refer to "capacity".
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//! These collections are generally built on top of an array. Optimally, this array would be
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//! exactly the right size to fit only the elements stored in the collection, but for the
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//! collection to do this would be very inefficient. If the backing array was exactly the
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//! right size at all times, then every time an element is inserted, the collection would
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//! have to grow the array to fit it. Due to the way memory is allocated and managed on most
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//! computers, this would almost surely require allocating an entirely new array and
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//! copying every single element from the old one into the new one. Hopefully you can
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//! see that this wouldn't be very efficient to do on every operation.
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//! Many collections provide several constructors and methods that refer to
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//! "capacity". These collections are generally built on top of an array.
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//! Optimally, this array would be exactly the right size to fit only the
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//! elements stored in the collection, but for the collection to do this would
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//! be very inefficient. If the backing array was exactly the right size at all
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//! times, then every time an element is inserted, the collection would have to
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//! grow the array to fit it. Due to the way memory is allocated and managed on
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//! most computers, this would almost surely require allocating an entirely new
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//! array and copying every single element from the old one into the new one.
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//! Hopefully you can see that this wouldn't be very efficient to do on every
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//! operation.
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//!
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//! Most collections therefore use an *amortized* allocation strategy. They generally let
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//! themselves have a fair amount of unoccupied space so that they only have to grow
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//! on occasion. When they do grow, they allocate a substantially larger array to move
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//! the elements into so that it will take a while for another grow to be required. While
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//! this strategy is great in general, it would be even better if the collection *never*
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//! had to resize its backing array. Unfortunately, the collection itself doesn't have
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//! enough information to do this itself. Therefore, it is up to us programmers to give it
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//! hints.
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//! Most collections therefore use an *amortized* allocation strategy. They
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//! generally let themselves have a fair amount of unoccupied space so that they
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//! only have to grow on occasion. When they do grow, they allocate a
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//! substantially larger array to move the elements into so that it will take a
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//! while for another grow to be required. While this strategy is great in
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//! general, it would be even better if the collection *never* had to resize its
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//! backing array. Unfortunately, the collection itself doesn't have enough
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//! information to do this itself. Therefore, it is up to us programmers to give
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//! it hints.
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//!
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//! Any `with_capacity` constructor will instruct the collection to allocate enough space
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//! for the specified number of elements. Ideally this will be for exactly that many
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//! elements, but some implementation details may prevent this. `Vec` and `VecDeque` can
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//! be relied on to allocate exactly the requested amount, though. Use `with_capacity`
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//! when you know exactly how many elements will be inserted, or at least have a
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//! reasonable upper-bound on that number.
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//! Any `with_capacity` constructor will instruct the collection to allocate
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//! enough space for the specified number of elements. Ideally this will be for
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//! exactly that many elements, but some implementation details may prevent
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//! this. `Vec` and `VecDeque` can be relied on to allocate exactly the
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//! requested amount, though. Use `with_capacity` when you know exactly how many
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//! elements will be inserted, or at least have a reasonable upper-bound on that
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//! number.
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//!
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//! When anticipating a large influx of elements, the `reserve` family of methods can
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//! be used to hint to the collection how much room it should make for the coming items.
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//! As with `with_capacity`, the precise behavior of these methods will be specific to
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//! the collection of interest.
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//! When anticipating a large influx of elements, the `reserve` family of
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//! methods can be used to hint to the collection how much room it should make
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//! for the coming items. As with `with_capacity`, the precise behavior of
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//! these methods will be specific to the collection of interest.
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//!
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//! For optimal performance, collections will generally avoid shrinking themselves.
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//! If you believe that a collection will not soon contain any more elements, or
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//! just really need the memory, the `shrink_to_fit` method prompts the collection
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//! to shrink the backing array to the minimum size capable of holding its elements.
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//! For optimal performance, collections will generally avoid shrinking
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//! themselves. If you believe that a collection will not soon contain any more
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//! elements, or just really need the memory, the `shrink_to_fit` method prompts
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//! the collection to shrink the backing array to the minimum size capable of
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//! holding its elements.
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//!
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//! Finally, if ever you're interested in what the actual capacity of the collection is,
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//! most collections provide a `capacity` method to query this information on demand.
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//! This can be useful for debugging purposes, or for use with the `reserve` methods.
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//! Finally, if ever you're interested in what the actual capacity of the
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//! collection is, most collections provide a `capacity` method to query this
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//! information on demand. This can be useful for debugging purposes, or for
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//! use with the `reserve` methods.
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//!
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//! ## Iterators
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//!
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//! Iterators are a powerful and robust mechanism used throughout Rust's standard
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//! libraries. Iterators provide a sequence of values in a generic, safe, efficient
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//! and convenient way. The contents of an iterator are usually *lazily* evaluated,
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//! so that only the values that are actually needed are ever actually produced, and
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//! no allocation need be done to temporarily store them. Iterators are primarily
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//! consumed using a `for` loop, although many functions also take iterators where
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//! a collection or sequence of values is desired.
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//! Iterators are a powerful and robust mechanism used throughout Rust's
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//! standard libraries. Iterators provide a sequence of values in a generic,
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//! safe, efficient and convenient way. The contents of an iterator are usually
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//! *lazily* evaluated, so that only the values that are actually needed are
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//! ever actually produced, and no allocation need be done to temporarily store
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//! them. Iterators are primarily consumed using a `for` loop, although many
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//! functions also take iterators where a collection or sequence of values is
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//! desired.
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//!
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//! All of the standard collections provide several iterators for performing bulk
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//! manipulation of their contents. The three primary iterators almost every collection
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//! should provide are `iter`, `iter_mut`, and `into_iter`. Some of these are not
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//! provided on collections where it would be unsound or unreasonable to provide them.
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//! All of the standard collections provide several iterators for performing
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//! bulk manipulation of their contents. The three primary iterators almost
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//! every collection should provide are `iter`, `iter_mut`, and `into_iter`.
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//! Some of these are not provided on collections where it would be unsound or
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//! unreasonable to provide them.
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//!
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//! `iter` provides an iterator of immutable references to all the contents of a
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//! collection in the most "natural" order. For sequence collections like `Vec`, this
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//! means the items will be yielded in increasing order of index starting at 0. For ordered
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//! collections like `BTreeMap`, this means that the items will be yielded in sorted order.
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//! For unordered collections like `HashMap`, the items will be yielded in whatever order
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//! the internal representation made most convenient. This is great for reading through
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//! all the contents of the collection.
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//! collection in the most "natural" order. For sequence collections like `Vec`,
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//! this means the items will be yielded in increasing order of index starting
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//! at 0. For ordered collections like `BTreeMap`, this means that the items
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//! will be yielded in sorted order. For unordered collections like `HashMap`,
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//! the items will be yielded in whatever order the internal representation made
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//! most convenient. This is great for reading through all the contents of the
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//! collection.
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//!
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//! ```
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//! let vec = vec![1, 2, 3, 4];
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//! }
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//! ```
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//!
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//! `iter_mut` provides an iterator of *mutable* references in the same order as `iter`.
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//! This is great for mutating all the contents of the collection.
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//! `iter_mut` provides an iterator of *mutable* references in the same order as
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//! `iter`. This is great for mutating all the contents of the collection.
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//!
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//! ```
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//! let mut vec = vec![1, 2, 3, 4];
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@ -226,13 +248,14 @@
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//! }
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//! ```
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//!
|
||||
//! `into_iter` transforms the actual collection into an iterator over its contents
|
||||
//! by-value. This is great when the collection itself is no longer needed, and the
|
||||
//! values are needed elsewhere. Using `extend` with `into_iter` is the main way that
|
||||
//! contents of one collection are moved into another. Calling `collect` on an iterator
|
||||
//! itself is also a great way to convert one collection into another. Both of these
|
||||
//! methods should internally use the capacity management tools discussed in the
|
||||
//! previous section to do this as efficiently as possible.
|
||||
//! `into_iter` transforms the actual collection into an iterator over its
|
||||
//! contents by-value. This is great when the collection itself is no longer
|
||||
//! needed, and the values are needed elsewhere. Using `extend` with `into_iter`
|
||||
//! is the main way that contents of one collection are moved into another.
|
||||
//! Calling `collect` on an iterator itself is also a great way to convert one
|
||||
//! collection into another. Both of these methods should internally use the
|
||||
//! capacity management tools discussed in the previous section to do this as
|
||||
//! efficiently as possible.
|
||||
//!
|
||||
//! ```
|
||||
//! let mut vec1 = vec![1, 2, 3, 4];
|
||||
|
@ -247,11 +270,12 @@
|
|||
//! let buf: VecDeque<_> = vec.into_iter().collect();
|
||||
//! ```
|
||||
//!
|
||||
//! Iterators also provide a series of *adapter* methods for performing common tasks to
|
||||
//! sequences. Among the adapters are functional favorites like `map`, `fold`, `skip`,
|
||||
//! and `take`. Of particular interest to collections is the `rev` adapter, that
|
||||
//! reverses any iterator that supports this operation. Most collections provide reversible
|
||||
//! iterators as the way to iterate over them in reverse order.
|
||||
//! Iterators also provide a series of *adapter* methods for performing common
|
||||
//! tasks to sequences. Among the adapters are functional favorites like `map`,
|
||||
//! `fold`, `skip`, and `take`. Of particular interest to collections is the
|
||||
//! `rev` adapter, that reverses any iterator that supports this operation. Most
|
||||
//! collections provide reversible iterators as the way to iterate over them in
|
||||
//! reverse order.
|
||||
//!
|
||||
//! ```
|
||||
//! let vec = vec![1, 2, 3, 4];
|
||||
|
@ -260,48 +284,50 @@
|
|||
//! }
|
||||
//! ```
|
||||
//!
|
||||
//! Several other collection methods also return iterators to yield a sequence of results
|
||||
//! but avoid allocating an entire collection to store the result in. This provides maximum
|
||||
//! flexibility as `collect` or `extend` can be called to "pipe" the sequence into any
|
||||
//! collection if desired. Otherwise, the sequence can be looped over with a `for` loop. The
|
||||
//! iterator can also be discarded after partial use, preventing the computation of the unused
|
||||
//! items.
|
||||
//! Several other collection methods also return iterators to yield a sequence
|
||||
//! of results but avoid allocating an entire collection to store the result in.
|
||||
//! This provides maximum flexibility as `collect` or `extend` can be called to
|
||||
//! "pipe" the sequence into any collection if desired. Otherwise, the sequence
|
||||
//! can be looped over with a `for` loop. The iterator can also be discarded
|
||||
//! after partial use, preventing the computation of the unused items.
|
||||
//!
|
||||
//! ## Entries
|
||||
//!
|
||||
//! The `entry` API is intended to provide an efficient mechanism for manipulating
|
||||
//! the contents of a map conditionally on the presence of a key or not. The primary
|
||||
//! motivating use case for this is to provide efficient accumulator maps. For instance,
|
||||
//! if one wishes to maintain a count of the number of times each key has been seen,
|
||||
//! they will have to perform some conditional logic on whether this is the first time
|
||||
//! the key has been seen or not. Normally, this would require a `find` followed by an
|
||||
//! `insert`, effectively duplicating the search effort on each insertion.
|
||||
//! The `entry` API is intended to provide an efficient mechanism for
|
||||
//! manipulating the contents of a map conditionally on the presence of a key or
|
||||
//! not. The primary motivating use case for this is to provide efficient
|
||||
//! accumulator maps. For instance, if one wishes to maintain a count of the
|
||||
//! number of times each key has been seen, they will have to perform some
|
||||
//! conditional logic on whether this is the first time the key has been seen or
|
||||
//! not. Normally, this would require a `find` followed by an `insert`,
|
||||
//! effectively duplicating the search effort on each insertion.
|
||||
//!
|
||||
//! When a user calls `map.entry(&key)`, the map will search for the key and then yield
|
||||
//! a variant of the `Entry` enum.
|
||||
//! When a user calls `map.entry(&key)`, the map will search for the key and
|
||||
//! then yield a variant of the `Entry` enum.
|
||||
//!
|
||||
//! If a `Vacant(entry)` is yielded, then the key *was not* found. In this case the
|
||||
//! only valid operation is to `insert` a value into the entry. When this is done,
|
||||
//! the vacant entry is consumed and converted into a mutable reference to the
|
||||
//! the value that was inserted. This allows for further manipulation of the value
|
||||
//! beyond the lifetime of the search itself. This is useful if complex logic needs to
|
||||
//! be performed on the value regardless of whether the value was just inserted.
|
||||
//! If a `Vacant(entry)` is yielded, then the key *was not* found. In this case
|
||||
//! the only valid operation is to `insert` a value into the entry. When this is
|
||||
//! done, the vacant entry is consumed and converted into a mutable reference to
|
||||
//! the the value that was inserted. This allows for further manipulation of the
|
||||
//! value beyond the lifetime of the search itself. This is useful if complex
|
||||
//! logic needs to be performed on the value regardless of whether the value was
|
||||
//! just inserted.
|
||||
//!
|
||||
//! If an `Occupied(entry)` is yielded, then the key *was* found. In this case, the user
|
||||
//! has several options: they can `get`, `insert`, or `remove` the value of the occupied
|
||||
//! entry. Additionally, they can convert the occupied entry into a mutable reference
|
||||
//! to its value, providing symmetry to the vacant `insert` case.
|
||||
//! If an `Occupied(entry)` is yielded, then the key *was* found. In this case,
|
||||
//! the user has several options: they can `get`, `insert`, or `remove` the
|
||||
//! value of the occupied entry. Additionally, they can convert the occupied
|
||||
//! entry into a mutable reference to its value, providing symmetry to the
|
||||
//! vacant `insert` case.
|
||||
//!
|
||||
//! ### Examples
|
||||
//!
|
||||
//! Here are the two primary ways in which `entry` is used. First, a simple example
|
||||
//! where the logic performed on the values is trivial.
|
||||
//! Here are the two primary ways in which `entry` is used. First, a simple
|
||||
//! example where the logic performed on the values is trivial.
|
||||
//!
|
||||
//! #### Counting the number of times each character in a string occurs
|
||||
//!
|
||||
//! ```
|
||||
//! # #![feature(collections)]
|
||||
//! use std::collections::btree_map::{BTreeMap, Entry};
|
||||
//! use std::collections::btree_map::BTreeMap;
|
||||
//!
|
||||
//! let mut count = BTreeMap::new();
|
||||
//! let message = "she sells sea shells by the sea shore";
|
||||
|
@ -318,15 +344,14 @@
|
|||
//! }
|
||||
//! ```
|
||||
//!
|
||||
//! When the logic to be performed on the value is more complex, we may simply use
|
||||
//! the `entry` API to ensure that the value is initialized, and perform the logic
|
||||
//! afterwards.
|
||||
//! When the logic to be performed on the value is more complex, we may simply
|
||||
//! use the `entry` API to ensure that the value is initialized, and perform the
|
||||
//! logic afterwards.
|
||||
//!
|
||||
//! #### Tracking the inebriation of customers at a bar
|
||||
//!
|
||||
//! ```
|
||||
//! # #![feature(collections)]
|
||||
//! use std::collections::btree_map::{BTreeMap, Entry};
|
||||
//! use std::collections::btree_map::BTreeMap;
|
||||
//!
|
||||
//! // A client of the bar. They have an id and a blood alcohol level.
|
||||
//! struct Person { id: u32, blood_alcohol: f32 }
|
||||
|
|
|
@ -96,14 +96,16 @@ pub struct WalkDir {
|
|||
|
||||
/// Options and flags which can be used to configure how a file is opened.
|
||||
///
|
||||
/// This builder exposes the ability to configure how a `File` is opened and what operations are
|
||||
/// permitted on the open file. The `File::open` and `File::create` methods are aliases for
|
||||
/// commonly used options using this builder.
|
||||
/// This builder exposes the ability to configure how a `File` is opened and
|
||||
/// what operations are permitted on the open file. The `File::open` and
|
||||
/// `File::create` methods are aliases for commonly used options using this
|
||||
/// builder.
|
||||
///
|
||||
/// Generally speaking, when using `OpenOptions`, you'll first call `new()`, then chain calls to
|
||||
/// methods to set each option, then call `open()`, passing the path of the file you're trying to
|
||||
/// open. This will give you a [`io::Result`][result] with a [`File`][file] inside that you can
|
||||
/// further operate on.
|
||||
/// Generally speaking, when using `OpenOptions`, you'll first call `new()`,
|
||||
/// then chain calls to methods to set each option, then call `open()`, passing
|
||||
/// the path of the file you're trying to open. This will give you a
|
||||
/// [`io::Result`][result] with a [`File`][file] inside that you can further
|
||||
/// operate on.
|
||||
///
|
||||
/// [result]: ../io/type.Result.html
|
||||
/// [file]: struct.File.html
|
||||
|
@ -113,16 +115,15 @@ pub struct WalkDir {
|
|||
/// Opening a file to read:
|
||||
///
|
||||
/// ```no_run
|
||||
/// use std::fs;
|
||||
/// use std::fs::OpenOptions;
|
||||
///
|
||||
/// let file = OpenOptions::new().read(true).open("foo.txt");
|
||||
/// ```
|
||||
///
|
||||
/// Opening a file for both reading and writing, as well as creating it if it doesn't exist:
|
||||
/// Opening a file for both reading and writing, as well as creating it if it
|
||||
/// doesn't exist:
|
||||
///
|
||||
/// ```
|
||||
/// use std::fs;
|
||||
/// use std::fs::OpenOptions;
|
||||
///
|
||||
/// let file = OpenOptions::new()
|
||||
|
@ -771,7 +772,9 @@ pub fn rename<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<()>
|
|||
/// ```no_run
|
||||
/// use std::fs;
|
||||
///
|
||||
/// fs::copy("foo.txt", "bar.txt");
|
||||
/// # fn foo() -> std::io::Result<()> {
|
||||
/// try!(fs::copy("foo.txt", "bar.txt"));
|
||||
/// # Ok(()) }
|
||||
/// ```
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub fn copy<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<u64> {
|
||||
|
|
|
@ -14,6 +14,7 @@
|
|||
//! by adding a glob import to the top of I/O heavy modules:
|
||||
//!
|
||||
//! ```
|
||||
//! # #![allow(unused_imports)]
|
||||
//! use std::io::prelude::*;
|
||||
//! ```
|
||||
//!
|
||||
|
|
|
@ -103,7 +103,8 @@
|
|||
html_favicon_url = "http://www.rust-lang.org/favicon.ico",
|
||||
html_root_url = "http://doc.rust-lang.org/nightly/",
|
||||
html_playground_url = "http://play.rust-lang.org/")]
|
||||
#![doc(test(no_crate_inject))]
|
||||
#![doc(test(no_crate_inject, attr(deny(warnings))))]
|
||||
#![doc(test(attr(allow(dead_code, deprecated, unused_variables, unused_mut))))]
|
||||
|
||||
#![feature(alloc)]
|
||||
#![feature(box_syntax)]
|
||||
|
|
|
@ -281,7 +281,6 @@ impl hash::Hash for SocketAddrV6 {
|
|||
/// Some examples:
|
||||
///
|
||||
/// ```no_run
|
||||
/// # #![feature(net)]
|
||||
/// use std::net::{SocketAddrV4, TcpStream, UdpSocket, TcpListener, Ipv4Addr};
|
||||
///
|
||||
/// fn main() {
|
||||
|
@ -302,7 +301,7 @@ impl hash::Hash for SocketAddrV6 {
|
|||
/// let tcp_l = TcpListener::bind("localhost:12345");
|
||||
///
|
||||
/// let mut udp_s = UdpSocket::bind(("127.0.0.1", port)).unwrap();
|
||||
/// udp_s.send_to(&[7], (ip, 23451));
|
||||
/// udp_s.send_to(&[7], (ip, 23451)).unwrap();
|
||||
/// }
|
||||
/// ```
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
|
|
|
@ -27,7 +27,6 @@ use sys_common::{AsInner, FromInner};
|
|||
/// # Examples
|
||||
///
|
||||
/// ```no_run
|
||||
/// # #![feature(net)]
|
||||
/// use std::io::prelude::*;
|
||||
/// use std::net::TcpStream;
|
||||
///
|
||||
|
@ -47,7 +46,6 @@ pub struct TcpStream(net_imp::TcpStream);
|
|||
/// # Examples
|
||||
///
|
||||
/// ```no_run
|
||||
/// # #![feature(net)]
|
||||
/// use std::net::{TcpListener, TcpStream};
|
||||
/// use std::thread;
|
||||
///
|
||||
|
|
|
@ -27,7 +27,6 @@ use sys_common::{AsInner, FromInner};
|
|||
/// # Examples
|
||||
///
|
||||
/// ```no_run
|
||||
/// # #![feature(net)]
|
||||
/// use std::net::UdpSocket;
|
||||
///
|
||||
/// # fn foo() -> std::io::Result<()> {
|
||||
|
|
|
@ -422,7 +422,6 @@ impl f32 {
|
|||
/// [subnormal][subnormal], or `NaN`.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(std_misc)]
|
||||
/// use std::f32;
|
||||
///
|
||||
/// let min = f32::MIN_POSITIVE; // 1.17549435e-38f32
|
||||
|
@ -856,7 +855,7 @@ impl f32 {
|
|||
/// Convert radians to degrees.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(std_misc, core)]
|
||||
/// # #![feature(std_misc)]
|
||||
/// use std::f32::{self, consts};
|
||||
///
|
||||
/// let angle = consts::PI;
|
||||
|
@ -987,7 +986,6 @@ impl f32 {
|
|||
/// * Else: `self - other`
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(std_misc)]
|
||||
/// use std::f32;
|
||||
///
|
||||
/// let x = 3.0f32;
|
||||
|
@ -1008,7 +1006,6 @@ impl f32 {
|
|||
/// Take the cubic root of a number.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(std_misc)]
|
||||
/// use std::f32;
|
||||
///
|
||||
/// let x = 8.0f32;
|
||||
|
@ -1210,8 +1207,6 @@ impl f32 {
|
|||
/// number is close to zero.
|
||||
///
|
||||
/// ```
|
||||
/// use std::f64;
|
||||
///
|
||||
/// let x = 7.0f64;
|
||||
///
|
||||
/// // e^(ln(7)) - 1
|
||||
|
|
|
@ -280,7 +280,6 @@ pub trait Float
|
|||
/// [subnormal][subnormal], or `NaN`.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(std_misc)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f32;
|
||||
///
|
||||
|
@ -307,7 +306,6 @@ pub trait Float
|
|||
/// predicate instead.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::{Float, FpCategory};
|
||||
/// use std::f32;
|
||||
///
|
||||
|
@ -417,7 +415,6 @@ pub trait Float
|
|||
/// number is `Float::nan()`.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(std_misc)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -441,7 +438,6 @@ pub trait Float
|
|||
/// - `Float::nan()` if the number is `Float::nan()`
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(std_misc)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -686,7 +682,6 @@ pub trait Float
|
|||
/// Convert radians to degrees.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(std_misc, core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64::consts;
|
||||
///
|
||||
|
@ -701,7 +696,7 @@ pub trait Float
|
|||
/// Convert degrees to radians.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(std_misc, core)]
|
||||
/// # #![feature(std_misc)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64::consts;
|
||||
///
|
||||
|
@ -849,7 +844,6 @@ pub trait Float
|
|||
/// Computes the sine of a number (in radians).
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -864,7 +858,6 @@ pub trait Float
|
|||
/// Computes the cosine of a number (in radians).
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -879,7 +872,6 @@ pub trait Float
|
|||
/// Computes the tangent of a number (in radians).
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -895,7 +887,6 @@ pub trait Float
|
|||
/// [-1, 1].
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -913,7 +904,6 @@ pub trait Float
|
|||
/// [-1, 1].
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -949,7 +939,6 @@ pub trait Float
|
|||
/// * `y < 0`: `arctan(y/x) - pi` -> `(-pi, -pi/2)`
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -975,7 +964,6 @@ pub trait Float
|
|||
/// `(sin(x), cos(x))`.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -1011,7 +999,6 @@ pub trait Float
|
|||
/// the operations were performed separately.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(std_misc, core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -1028,7 +1015,6 @@ pub trait Float
|
|||
/// Hyperbolic sine function.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -1047,7 +1033,6 @@ pub trait Float
|
|||
/// Hyperbolic cosine function.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -1066,7 +1051,6 @@ pub trait Float
|
|||
/// Hyperbolic tangent function.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
@ -1113,7 +1097,6 @@ pub trait Float
|
|||
/// Inverse hyperbolic tangent function.
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(core)]
|
||||
/// use std::num::Float;
|
||||
/// use std::f64;
|
||||
///
|
||||
|
|
|
@ -48,7 +48,7 @@
|
|||
//! * Read lines from stdin
|
||||
//!
|
||||
//! ```rust
|
||||
//! # #![feature(old_io, old_path)]
|
||||
//! # #![feature(old_io)]
|
||||
//! use std::old_io as io;
|
||||
//! use std::old_io::*;
|
||||
//!
|
||||
|
|
|
@ -414,7 +414,7 @@ pub struct ParseError;
|
|||
/// Some examples:
|
||||
///
|
||||
/// ```rust,no_run
|
||||
/// # #![feature(old_io, core, convert)]
|
||||
/// # #![feature(old_io)]
|
||||
/// # #![allow(unused_must_use)]
|
||||
///
|
||||
/// use std::old_io::{TcpStream, TcpListener};
|
||||
|
|
|
@ -191,7 +191,7 @@ impl UnixListener {
|
|||
/// let server = Path::new("/path/to/my/socket");
|
||||
/// let stream = UnixListener::bind(&server);
|
||||
/// for mut client in stream.listen().incoming() {
|
||||
/// client.write(&[1, 2, 3, 4]);
|
||||
/// let _ = client.write(&[1, 2, 3, 4]);
|
||||
/// }
|
||||
/// # }
|
||||
/// ```
|
||||
|
|
|
@ -367,7 +367,7 @@ impl Command {
|
|||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(old_io, core, convert)]
|
||||
/// # #![feature(old_io)]
|
||||
/// use std::old_io::Command;
|
||||
///
|
||||
/// let output = match Command::new("cat").arg("foot.txt").output() {
|
||||
|
|
|
@ -144,12 +144,10 @@ pub trait GenericPath: Clone + GenericPathUnsafe {
|
|||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// ```no_run
|
||||
/// # #![feature(old_path)]
|
||||
/// use std::old_path::{Path, GenericPath};
|
||||
/// # foo();
|
||||
/// # #[cfg(windows)] fn foo() {}
|
||||
/// # #[cfg(unix)] fn foo() {
|
||||
/// # fn main() {
|
||||
/// use std::old_path::Path;
|
||||
/// let path = Path::new("foo/bar");
|
||||
/// # }
|
||||
/// ```
|
||||
|
@ -170,12 +168,10 @@ pub trait GenericPath: Clone + GenericPathUnsafe {
|
|||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// ```no_run
|
||||
/// # #![feature(old_path)]
|
||||
/// use std::old_path::{Path, GenericPath};
|
||||
/// # foo();
|
||||
/// # #[cfg(windows)] fn foo() {}
|
||||
/// # #[cfg(unix)] fn foo() {
|
||||
/// # fn main() {
|
||||
/// use std::old_path::Path;
|
||||
/// let x: &[u8] = b"foo\0";
|
||||
/// assert!(Path::new_opt(x).is_none());
|
||||
/// # }
|
||||
|
|
|
@ -38,8 +38,6 @@ use thread;
|
|||
/// # Examples
|
||||
///
|
||||
/// ```should_panic
|
||||
/// # #![feature(process)]
|
||||
///
|
||||
/// use std::process::Command;
|
||||
///
|
||||
/// let output = Command::new("/bin/cat").arg("file.txt").output().unwrap_or_else(|e| {
|
||||
|
@ -267,10 +265,8 @@ impl Command {
|
|||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(process)]
|
||||
/// use std::process::Command;
|
||||
///
|
||||
/// let output = Command::new("cat").arg("foot.txt").output().unwrap_or_else(|e| {
|
||||
/// let output = Command::new("cat").arg("foo.txt").output().unwrap_or_else(|e| {
|
||||
/// panic!("failed to execute process: {}", e)
|
||||
/// });
|
||||
///
|
||||
|
@ -291,7 +287,6 @@ impl Command {
|
|||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// # #![feature(process)]
|
||||
/// use std::process::Command;
|
||||
///
|
||||
/// let status = Command::new("ls").status().unwrap_or_else(|e| {
|
||||
|
|
|
@ -99,6 +99,7 @@
|
|||
//! `println!` and `panic!` for the child thread:
|
||||
//!
|
||||
//! ```rust
|
||||
//! # #![allow(unused_must_use)]
|
||||
//! use std::thread;
|
||||
//!
|
||||
//! thread::Builder::new().name("child1".to_string()).spawn(move || {
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue