danvics/oxipng
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
oxipng/doc/bitflags/__core/collections/struct.BTreeMap.html

588 lines
No EOL
77 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="generator" content="rustdoc">
<meta name="description" content="API documentation for the Rust `BTreeMap` struct in crate `bitflags`.">
<meta name="keywords" content="rust, rustlang, rust-lang, BTreeMap">
<title>bitflags::__core::collections::BTreeMap - Rust</title>
<link rel="stylesheet" type="text/css" href="../../../rustdoc.css">
<link rel="stylesheet" type="text/css" href="../../../main.css">
</head>
<body class="rustdoc">
<!--[if lte IE 8]>
<div class="warning">
This old browser is unsupported and will most likely display funky
things.
</div>
<![endif]-->
<nav class="sidebar">
<p class='location'><a href='../../index.html'>bitflags</a>::<wbr><a href='../index.html'>__core</a>::<wbr><a href='index.html'>collections</a></p><script>window.sidebarCurrent = {name: 'BTreeMap', ty: 'struct', relpath: ''};</script><script defer src="sidebar-items.js"></script>
</nav>
<nav class="sub">
<form class="search-form js-only">
<div class="search-container">
<input class="search-input" name="search"
autocomplete="off"
placeholder="Click or press ‘S’ to search, ‘?’ for more options…"
type="search">
</div>
</form>
</nav>
<section id='main' class="content struct">
<h1 class='fqn'><span class='in-band'>Struct <a href='../../index.html'>bitflags</a>::<wbr><a href='../index.html'>__core</a>::<wbr><a href='index.html'>collections</a>::<wbr><a class='struct' href=''>BTreeMap</a></span><span class='out-of-band'><span id='render-detail'>
<a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">
[<span class='inner'>&#x2212;</span>]
</a>
</span><a id='src-923' class='srclink' href='https://doc.rust-lang.org/nightly/collections/btree/map/struct.BTreeMap.html?gotosrc=923' title='goto source code'>[src]</a></span></h1>
<pre class='rust struct'>pub struct BTreeMap&lt;K, V&gt; {
// some fields omitted
}</pre><span class="since">1.0.0</span><div class='docblock'><p>A map based on a B-Tree.</p>
<p>B-Trees represent a fundamental compromise between cache-efficiency and actually minimizing
the amount of work performed in a search. In theory, a binary search tree (BST) is the optimal
choice for a sorted map, as a perfectly balanced BST performs the theoretical minimum amount of
comparisons necessary to find an element (log<sub>2</sub>n). However, in practice the way this
is done is <em>very</em> inefficient for modern computer architectures. In particular, every element
is stored in its own individually heap-allocated node. This means that every single insertion
triggers a heap-allocation, and every single comparison should be a cache-miss. Since these
are both notably expensive things to do in practice, we are forced to at very least reconsider
the BST strategy.</p>
<p>A B-Tree instead makes each node contain B-1 to 2B-1 elements in a contiguous array. By doing
this, we reduce the number of allocations by a factor of B, and improve cache efficiency in
searches. However, this does mean that searches will have to do <em>more</em> comparisons on average.
The precise number of comparisons depends on the node search strategy used. For optimal cache
efficiency, one could search the nodes linearly. For optimal comparisons, one could search
the node using binary search. As a compromise, one could also perform a linear search
that initially only checks every i<sup>th</sup> element for some choice of i.</p>
<p>Currently, our implementation simply performs naive linear search. This provides excellent
performance on <em>small</em> nodes of elements which are cheap to compare. However in the future we
would like to further explore choosing the optimal search strategy based on the choice of B,
and possibly other factors. Using linear search, searching for a random element is expected
to take O(B log<sub>B</sub>n) comparisons, which is generally worse than a BST. In practice,
however, performance is excellent.</p>
<p>It is a logic error for a key to be modified in such a way that the key&#39;s ordering relative to
any other key, as determined by the <code>Ord</code> trait, changes while it is in the map. This is
normally only possible through <code>Cell</code>, <code>RefCell</code>, global state, I/O, or unsafe code.</p>
<h1 id='examples' class='section-header'><a href='#examples'>Examples</a></h1>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='comment'>// type inference lets us omit an explicit type signature (which</span>
<span class='comment'>// would be `BTreeMap&lt;&amp;str, &amp;str&gt;` in this example).</span>
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>movie_reviews</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='comment'>// review some books.</span>
<span class='ident'>movie_reviews</span>.<span class='ident'>insert</span>(<span class='string'>&quot;Office Space&quot;</span>, <span class='string'>&quot;Deals with real issues in the workplace.&quot;</span>);
<span class='ident'>movie_reviews</span>.<span class='ident'>insert</span>(<span class='string'>&quot;Pulp Fiction&quot;</span>, <span class='string'>&quot;Masterpiece.&quot;</span>);
<span class='ident'>movie_reviews</span>.<span class='ident'>insert</span>(<span class='string'>&quot;The Godfather&quot;</span>, <span class='string'>&quot;Very enjoyable.&quot;</span>);
<span class='ident'>movie_reviews</span>.<span class='ident'>insert</span>(<span class='string'>&quot;The Blues Brothers&quot;</span>, <span class='string'>&quot;Eye lyked it alot.&quot;</span>);
<span class='comment'>// check for a specific one.</span>
<span class='kw'>if</span> <span class='op'>!</span><span class='ident'>movie_reviews</span>.<span class='ident'>contains_key</span>(<span class='string'>&quot;Les Misérables&quot;</span>) {
<span class='macro'>println</span><span class='macro'>!</span>(<span class='string'>&quot;We&#39;ve got {} reviews, but Les Misérables ain&#39;t one.&quot;</span>,
<span class='ident'>movie_reviews</span>.<span class='ident'>len</span>());
}
<span class='comment'>// oops, this review has a lot of spelling mistakes, let&#39;s delete it.</span>
<span class='ident'>movie_reviews</span>.<span class='ident'>remove</span>(<span class='string'>&quot;The Blues Brothers&quot;</span>);
<span class='comment'>// look up the values associated with some keys.</span>
<span class='kw'>let</span> <span class='ident'>to_find</span> <span class='op'>=</span> [<span class='string'>&quot;Up!&quot;</span>, <span class='string'>&quot;Office Space&quot;</span>];
<span class='kw'>for</span> <span class='ident'>book</span> <span class='kw'>in</span> <span class='kw-2'>&amp;</span><span class='ident'>to_find</span> {
<span class='kw'>match</span> <span class='ident'>movie_reviews</span>.<span class='ident'>get</span>(<span class='ident'>book</span>) {
<span class='prelude-val'>Some</span>(<span class='ident'>review</span>) <span class='op'>=&gt;</span> <span class='macro'>println</span><span class='macro'>!</span>(<span class='string'>&quot;{}: {}&quot;</span>, <span class='ident'>book</span>, <span class='ident'>review</span>),
<span class='prelude-val'>None</span> <span class='op'>=&gt;</span> <span class='macro'>println</span><span class='macro'>!</span>(<span class='string'>&quot;{} is unreviewed.&quot;</span>, <span class='ident'>book</span>)
}
}
<span class='comment'>// iterate over everything.</span>
<span class='kw'>for</span> (<span class='ident'>movie</span>, <span class='ident'>review</span>) <span class='kw'>in</span> <span class='kw-2'>&amp;</span><span class='ident'>movie_reviews</span> {
<span class='macro'>println</span><span class='macro'>!</span>(<span class='string'>&quot;{}: \&quot;{}\&quot;&quot;</span>, <span class='ident'>movie</span>, <span class='ident'>review</span>);
}</pre>
<p><code>BTreeMap</code> also implements an <a href="#method.entry"><code>Entry API</code></a>, which allows
for more complex methods of getting, setting, updating and removing keys and
their values:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='comment'>// type inference lets us omit an explicit type signature (which</span>
<span class='comment'>// would be `BTreeMap&lt;&amp;str, u8&gt;` in this example).</span>
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>player_stats</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='kw'>fn</span> <span class='ident'>random_stat_buff</span>() <span class='op'>-&gt;</span> <span class='ident'>u8</span> {
<span class='comment'>// could actually return some random value here - let&#39;s just return</span>
<span class='comment'>// some fixed value for now</span>
<span class='number'>42</span>
}
<span class='comment'>// insert a key only if it doesn&#39;t already exist</span>
<span class='ident'>player_stats</span>.<span class='ident'>entry</span>(<span class='string'>&quot;health&quot;</span>).<span class='ident'>or_insert</span>(<span class='number'>100</span>);
<span class='comment'>// insert a key using a function that provides a new value only if it</span>
<span class='comment'>// doesn&#39;t already exist</span>
<span class='ident'>player_stats</span>.<span class='ident'>entry</span>(<span class='string'>&quot;defence&quot;</span>).<span class='ident'>or_insert_with</span>(<span class='ident'>random_stat_buff</span>);
<span class='comment'>// update a key, guarding against the key possibly not being set</span>
<span class='kw'>let</span> <span class='ident'>stat</span> <span class='op'>=</span> <span class='ident'>player_stats</span>.<span class='ident'>entry</span>(<span class='string'>&quot;attack&quot;</span>).<span class='ident'>or_insert</span>(<span class='number'>100</span>);
<span class='op'>*</span><span class='ident'>stat</span> <span class='op'>+=</span> <span class='ident'>random_stat_buff</span>();</pre>
</div><h2 id='methods'>Methods</h2><h3 class='impl'><code>impl&lt;K, V&gt; <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a></span></code></h3><div class='impl-items'><h4 id='method.new' class='method'><code>fn <a href='#method.new' class='fnname'>new</a>() -&gt; <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;</code></h4>
<div class='docblock'><p>Makes a new empty BTreeMap with a reasonable choice for B.</p>
<h1 id='examples-1' class='section-header'><a href='#examples-1'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>map</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='comment'>// entries can now be inserted into the empty map</span>
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);</pre>
</div><h4 id='method.clear' class='method'><code>fn <a href='#method.clear' class='fnname'>clear</a>(&amp;mut self)</code></h4>
<div class='docblock'><p>Clears the map, removing all values.</p>
<h1 id='examples-2' class='section-header'><a href='#examples-2'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>a</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);
<span class='ident'>a</span>.<span class='ident'>clear</span>();
<span class='macro'>assert</span><span class='macro'>!</span>(<span class='ident'>a</span>.<span class='ident'>is_empty</span>());</pre>
</div><h4 id='method.get' class='method'><code>fn <a href='#method.get' class='fnname'>get</a>&lt;Q&gt;(&amp;self, key: &amp;Q) -&gt; <a class='enum' href='../../../bitflags/__core/option/enum.Option.html' title='bitflags::__core::option::Option'>Option</a>&lt;&amp;V&gt; <span class='where'>where Q: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> + ?<a class='trait' href='../../../bitflags/__core/marker/trait.Sized.html' title='bitflags::__core::marker::Sized'>Sized</a>, K: <a class='trait' href='../../../bitflags/__core/borrow/trait.Borrow.html' title='bitflags::__core::borrow::Borrow'>Borrow</a>&lt;Q&gt;</span></code></h4>
<div class='docblock'><p>Returns a reference to the value corresponding to the key.</p>
<p>The key may be any borrowed form of the map&#39;s key type, but the ordering
on the borrowed form <em>must</em> match the ordering on the key type.</p>
<h1 id='examples-3' class='section-header'><a href='#examples-3'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>map</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>.<span class='ident'>get</span>(<span class='kw-2'>&amp;</span><span class='number'>1</span>), <span class='prelude-val'>Some</span>(<span class='kw-2'>&amp;</span><span class='string'>&quot;a&quot;</span>));
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>.<span class='ident'>get</span>(<span class='kw-2'>&amp;</span><span class='number'>2</span>), <span class='prelude-val'>None</span>);</pre>
</div><h4 id='method.contains_key' class='method'><code>fn <a href='#method.contains_key' class='fnname'>contains_key</a>&lt;Q&gt;(&amp;self, key: &amp;Q) -&gt; <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.bool.html'>bool</a> <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/borrow/trait.Borrow.html' title='bitflags::__core::borrow::Borrow'>Borrow</a>&lt;Q&gt;, Q: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> + ?<a class='trait' href='../../../bitflags/__core/marker/trait.Sized.html' title='bitflags::__core::marker::Sized'>Sized</a></span></code></h4>
<div class='docblock'><p>Returns true if the map contains a value for the specified key.</p>
<p>The key may be any borrowed form of the map&#39;s key type, but the ordering
on the borrowed form <em>must</em> match the ordering on the key type.</p>
<h1 id='examples-4' class='section-header'><a href='#examples-4'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>map</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>.<span class='ident'>contains_key</span>(<span class='kw-2'>&amp;</span><span class='number'>1</span>), <span class='boolval'>true</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>.<span class='ident'>contains_key</span>(<span class='kw-2'>&amp;</span><span class='number'>2</span>), <span class='boolval'>false</span>);</pre>
</div><h4 id='method.get_mut' class='method'><code>fn <a href='#method.get_mut' class='fnname'>get_mut</a>&lt;Q&gt;(&amp;mut self, key: &amp;Q) -&gt; <a class='enum' href='../../../bitflags/__core/option/enum.Option.html' title='bitflags::__core::option::Option'>Option</a>&lt;&amp;mut V&gt; <span class='where'>where Q: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> + ?<a class='trait' href='../../../bitflags/__core/marker/trait.Sized.html' title='bitflags::__core::marker::Sized'>Sized</a>, K: <a class='trait' href='../../../bitflags/__core/borrow/trait.Borrow.html' title='bitflags::__core::borrow::Borrow'>Borrow</a>&lt;Q&gt;</span></code></h4>
<div class='docblock'><p>Returns a mutable reference to the value corresponding to the key.</p>
<p>The key may be any borrowed form of the map&#39;s key type, but the ordering
on the borrowed form <em>must</em> match the ordering on the key type.</p>
<h1 id='examples-5' class='section-header'><a href='#examples-5'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>map</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);
<span class='kw'>if</span> <span class='kw'>let</span> <span class='prelude-val'>Some</span>(<span class='ident'>x</span>) <span class='op'>=</span> <span class='ident'>map</span>.<span class='ident'>get_mut</span>(<span class='kw-2'>&amp;</span><span class='number'>1</span>) {
<span class='op'>*</span><span class='ident'>x</span> <span class='op'>=</span> <span class='string'>&quot;b&quot;</span>;
}
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>[<span class='kw-2'>&amp;</span><span class='number'>1</span>], <span class='string'>&quot;b&quot;</span>);</pre>
</div><h4 id='method.insert' class='method'><code>fn <a href='#method.insert' class='fnname'>insert</a>(&amp;mut self, key: K, value: V) -&gt; <a class='enum' href='../../../bitflags/__core/option/enum.Option.html' title='bitflags::__core::option::Option'>Option</a>&lt;V&gt;</code></h4>
<div class='docblock'><p>Inserts a key-value pair into the map.</p>
<p>If the map did not have this key present, <code>None</code> is returned.</p>
<p>If the map did have this key present, the value is updated, and the old
value is returned. The key is not updated, though; this matters for
types that can be <code>==</code> without being identical. See the <a href="index.html#insert-and-complex-keys">module-level
documentation</a> for more.</p>
<h1 id='examples-6' class='section-header'><a href='#examples-6'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>map</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>37</span>, <span class='string'>&quot;a&quot;</span>), <span class='prelude-val'>None</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>.<span class='ident'>is_empty</span>(), <span class='boolval'>false</span>);
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>37</span>, <span class='string'>&quot;b&quot;</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>37</span>, <span class='string'>&quot;c&quot;</span>), <span class='prelude-val'>Some</span>(<span class='string'>&quot;b&quot;</span>));
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>[<span class='kw-2'>&amp;</span><span class='number'>37</span>], <span class='string'>&quot;c&quot;</span>);</pre>
</div><h4 id='method.remove' class='method'><code>fn <a href='#method.remove' class='fnname'>remove</a>&lt;Q&gt;(&amp;mut self, key: &amp;Q) -&gt; <a class='enum' href='../../../bitflags/__core/option/enum.Option.html' title='bitflags::__core::option::Option'>Option</a>&lt;V&gt; <span class='where'>where Q: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> + ?<a class='trait' href='../../../bitflags/__core/marker/trait.Sized.html' title='bitflags::__core::marker::Sized'>Sized</a>, K: <a class='trait' href='../../../bitflags/__core/borrow/trait.Borrow.html' title='bitflags::__core::borrow::Borrow'>Borrow</a>&lt;Q&gt;</span></code></h4>
<div class='docblock'><p>Removes a key from the map, returning the value at the key if the key
was previously in the map.</p>
<p>The key may be any borrowed form of the map&#39;s key type, but the ordering
on the borrowed form <em>must</em> match the ordering on the key type.</p>
<h1 id='examples-7' class='section-header'><a href='#examples-7'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>map</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>.<span class='ident'>remove</span>(<span class='kw-2'>&amp;</span><span class='number'>1</span>), <span class='prelude-val'>Some</span>(<span class='string'>&quot;a&quot;</span>));
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>map</span>.<span class='ident'>remove</span>(<span class='kw-2'>&amp;</span><span class='number'>1</span>), <span class='prelude-val'>None</span>);</pre>
</div><h4 id='method.append' class='method'><code>fn <a href='#method.append' class='fnname'>append</a>(&amp;mut self, other: &amp;mut <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;)</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>btree_append</code>)<p>: recently added as part of collections reform 2</p>
</em></div><div class='docblock'><p>Moves all elements from <code>other</code> into <code>Self</code>, leaving <code>other</code> empty.</p>
<h1 id='examples-8' class='section-header'><a href='#examples-8'>Examples</a></h1>
<pre class='rust rust-example-rendered'>
<span class='attribute'>#<span class='op'>!</span>[<span class='ident'>feature</span>(<span class='ident'>btree_append</span>)]</span>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>a</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>2</span>, <span class='string'>&quot;b&quot;</span>);
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>3</span>, <span class='string'>&quot;c&quot;</span>);
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>b</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>b</span>.<span class='ident'>insert</span>(<span class='number'>3</span>, <span class='string'>&quot;d&quot;</span>);
<span class='ident'>b</span>.<span class='ident'>insert</span>(<span class='number'>4</span>, <span class='string'>&quot;e&quot;</span>);
<span class='ident'>b</span>.<span class='ident'>insert</span>(<span class='number'>5</span>, <span class='string'>&quot;f&quot;</span>);
<span class='ident'>a</span>.<span class='ident'>append</span>(<span class='kw-2'>&amp;</span><span class='kw-2'>mut</span> <span class='ident'>b</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>a</span>.<span class='ident'>len</span>(), <span class='number'>5</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>b</span>.<span class='ident'>len</span>(), <span class='number'>0</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>a</span>[<span class='kw-2'>&amp;</span><span class='number'>1</span>], <span class='string'>&quot;a&quot;</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>a</span>[<span class='kw-2'>&amp;</span><span class='number'>2</span>], <span class='string'>&quot;b&quot;</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>a</span>[<span class='kw-2'>&amp;</span><span class='number'>3</span>], <span class='string'>&quot;d&quot;</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>a</span>[<span class='kw-2'>&amp;</span><span class='number'>4</span>], <span class='string'>&quot;e&quot;</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>a</span>[<span class='kw-2'>&amp;</span><span class='number'>5</span>], <span class='string'>&quot;f&quot;</span>);</pre>
</div><h4 id='method.range' class='method'><code>fn <a href='#method.range' class='fnname'>range</a>&lt;Min, Max&gt;(&amp;self, min: <a class='enum' href='../../../bitflags/__core/collections/enum.Bound.html' title='bitflags::__core::collections::Bound'>Bound</a>&lt;&amp;Min&gt;, max: <a class='enum' href='../../../bitflags/__core/collections/enum.Bound.html' title='bitflags::__core::collections::Bound'>Bound</a>&lt;&amp;Max&gt;) -&gt; <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.Range.html' title='bitflags::__core::collections::btree_map::Range'>Range</a>&lt;K, V&gt; <span class='where'>where Min: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> + ?<a class='trait' href='../../../bitflags/__core/marker/trait.Sized.html' title='bitflags::__core::marker::Sized'>Sized</a>, K: <a class='trait' href='../../../bitflags/__core/borrow/trait.Borrow.html' title='bitflags::__core::borrow::Borrow'>Borrow</a>&lt;Min&gt; + <a class='trait' href='../../../bitflags/__core/borrow/trait.Borrow.html' title='bitflags::__core::borrow::Borrow'>Borrow</a>&lt;Max&gt;, Max: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> + ?<a class='trait' href='../../../bitflags/__core/marker/trait.Sized.html' title='bitflags::__core::marker::Sized'>Sized</a></span></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>btree_range</code>)<p>: matches collection reform specification, waiting for dust to settle</p>
</em></div><div class='docblock'><p>Constructs a double-ended iterator over a sub-range of elements in the map, starting
at min, and ending at max. If min is <code>Unbounded</code>, then it will be treated as &quot;negative
infinity&quot;, and if max is <code>Unbounded</code>, then it will be treated as &quot;positive infinity&quot;.
Thus range(Unbounded, Unbounded) will yield the whole collection.</p>
<h1 id='examples-9' class='section-header'><a href='#examples-9'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='attribute'>#<span class='op'>!</span>[<span class='ident'>feature</span>(<span class='ident'>btree_range</span>, <span class='ident'>collections_bound</span>)]</span>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>Bound</span>::{<span class='ident'>Included</span>, <span class='ident'>Unbounded</span>};
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>map</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>3</span>, <span class='string'>&quot;a&quot;</span>);
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>5</span>, <span class='string'>&quot;b&quot;</span>);
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>8</span>, <span class='string'>&quot;c&quot;</span>);
<span class='kw'>for</span> (<span class='kw-2'>&amp;</span><span class='ident'>key</span>, <span class='kw-2'>&amp;</span><span class='ident'>value</span>) <span class='kw'>in</span> <span class='ident'>map</span>.<span class='ident'>range</span>(<span class='ident'>Included</span>(<span class='kw-2'>&amp;</span><span class='number'>4</span>), <span class='ident'>Included</span>(<span class='kw-2'>&amp;</span><span class='number'>8</span>)) {
<span class='macro'>println</span><span class='macro'>!</span>(<span class='string'>&quot;{}: {}&quot;</span>, <span class='ident'>key</span>, <span class='ident'>value</span>);
}
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='prelude-val'>Some</span>((<span class='kw-2'>&amp;</span><span class='number'>5</span>, <span class='kw-2'>&amp;</span><span class='string'>&quot;b&quot;</span>)), <span class='ident'>map</span>.<span class='ident'>range</span>(<span class='ident'>Included</span>(<span class='kw-2'>&amp;</span><span class='number'>4</span>), <span class='ident'>Unbounded</span>).<span class='ident'>next</span>());</pre>
</div><h4 id='method.range_mut' class='method'><code>fn <a href='#method.range_mut' class='fnname'>range_mut</a>&lt;Min, Max&gt;(&amp;mut self, min: <a class='enum' href='../../../bitflags/__core/collections/enum.Bound.html' title='bitflags::__core::collections::Bound'>Bound</a>&lt;&amp;Min&gt;, max: <a class='enum' href='../../../bitflags/__core/collections/enum.Bound.html' title='bitflags::__core::collections::Bound'>Bound</a>&lt;&amp;Max&gt;) -&gt; <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.RangeMut.html' title='bitflags::__core::collections::btree_map::RangeMut'>RangeMut</a>&lt;K, V&gt; <span class='where'>where Min: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> + ?<a class='trait' href='../../../bitflags/__core/marker/trait.Sized.html' title='bitflags::__core::marker::Sized'>Sized</a>, K: <a class='trait' href='../../../bitflags/__core/borrow/trait.Borrow.html' title='bitflags::__core::borrow::Borrow'>Borrow</a>&lt;Min&gt; + <a class='trait' href='../../../bitflags/__core/borrow/trait.Borrow.html' title='bitflags::__core::borrow::Borrow'>Borrow</a>&lt;Max&gt;, Max: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> + ?<a class='trait' href='../../../bitflags/__core/marker/trait.Sized.html' title='bitflags::__core::marker::Sized'>Sized</a></span></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>btree_range</code>)<p>: matches collection reform specification, waiting for dust to settle</p>
</em></div><div class='docblock'><p>Constructs a mutable double-ended iterator over a sub-range of elements in the map, starting
at min, and ending at max. If min is <code>Unbounded</code>, then it will be treated as &quot;negative
infinity&quot;, and if max is <code>Unbounded</code>, then it will be treated as &quot;positive infinity&quot;.
Thus range(Unbounded, Unbounded) will yield the whole collection.</p>
<h1 id='examples-10' class='section-header'><a href='#examples-10'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='attribute'>#<span class='op'>!</span>[<span class='ident'>feature</span>(<span class='ident'>btree_range</span>, <span class='ident'>collections_bound</span>)]</span>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>Bound</span>::{<span class='ident'>Included</span>, <span class='ident'>Excluded</span>};
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>map</span>: <span class='ident'>BTreeMap</span><span class='op'>&lt;</span><span class='kw-2'>&amp;</span><span class='ident'>str</span>, <span class='ident'>i32</span><span class='op'>&gt;</span> <span class='op'>=</span> [<span class='string'>&quot;Alice&quot;</span>, <span class='string'>&quot;Bob&quot;</span>, <span class='string'>&quot;Carol&quot;</span>, <span class='string'>&quot;Cheryl&quot;</span>].<span class='ident'>iter</span>()
.<span class='ident'>map</span>(<span class='op'>|</span><span class='kw-2'>&amp;</span><span class='ident'>s</span><span class='op'>|</span> (<span class='ident'>s</span>, <span class='number'>0</span>))
.<span class='ident'>collect</span>();
<span class='kw'>for</span> (_, <span class='ident'>balance</span>) <span class='kw'>in</span> <span class='ident'>map</span>.<span class='ident'>range_mut</span>(<span class='ident'>Included</span>(<span class='string'>&quot;B&quot;</span>), <span class='ident'>Excluded</span>(<span class='string'>&quot;Cheryl&quot;</span>)) {
<span class='op'>*</span><span class='ident'>balance</span> <span class='op'>+=</span> <span class='number'>100</span>;
}
<span class='kw'>for</span> (<span class='ident'>name</span>, <span class='ident'>balance</span>) <span class='kw'>in</span> <span class='kw-2'>&amp;</span><span class='ident'>map</span> {
<span class='macro'>println</span><span class='macro'>!</span>(<span class='string'>&quot;{} =&gt; {}&quot;</span>, <span class='ident'>name</span>, <span class='ident'>balance</span>);
}</pre>
</div><h4 id='method.entry' class='method'><code>fn <a href='#method.entry' class='fnname'>entry</a>(&amp;mut self, key: K) -&gt; <a class='enum' href='../../../bitflags/__core/collections/btree_map/enum.Entry.html' title='bitflags::__core::collections::btree_map::Entry'>Entry</a>&lt;K, V&gt;</code></h4>
<div class='docblock'><p>Gets the given key&#39;s corresponding entry in the map for in-place manipulation.</p>
<h1 id='examples-11' class='section-header'><a href='#examples-11'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>count</span>: <span class='ident'>BTreeMap</span><span class='op'>&lt;</span><span class='kw-2'>&amp;</span><span class='ident'>str</span>, <span class='ident'>usize</span><span class='op'>&gt;</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='comment'>// count the number of occurrences of letters in the vec</span>
<span class='kw'>for</span> <span class='ident'>x</span> <span class='kw'>in</span> <span class='macro'>vec</span><span class='macro'>!</span>[<span class='string'>&quot;a&quot;</span>,<span class='string'>&quot;b&quot;</span>,<span class='string'>&quot;a&quot;</span>,<span class='string'>&quot;c&quot;</span>,<span class='string'>&quot;a&quot;</span>,<span class='string'>&quot;b&quot;</span>] {
<span class='op'>*</span><span class='ident'>count</span>.<span class='ident'>entry</span>(<span class='ident'>x</span>).<span class='ident'>or_insert</span>(<span class='number'>0</span>) <span class='op'>+=</span> <span class='number'>1</span>;
}
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>count</span>[<span class='string'>&quot;a&quot;</span>], <span class='number'>3</span>);</pre>
</div></div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;</code></h3><div class='impl-items'><h4 id='method.iter' class='method'><code>fn <a href='#method.iter' class='fnname'>iter</a>(&amp;self) -&gt; <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.Iter.html' title='bitflags::__core::collections::btree_map::Iter'>Iter</a>&lt;K, V&gt;</code></h4>
<div class='docblock'><p>Gets an iterator over the entries of the map, sorted by key.</p>
<h1 id='examples-12' class='section-header'><a href='#examples-12'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>map</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>3</span>, <span class='string'>&quot;c&quot;</span>);
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>2</span>, <span class='string'>&quot;b&quot;</span>);
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);
<span class='kw'>for</span> (<span class='ident'>key</span>, <span class='ident'>value</span>) <span class='kw'>in</span> <span class='ident'>map</span>.<span class='ident'>iter</span>() {
<span class='macro'>println</span><span class='macro'>!</span>(<span class='string'>&quot;{}: {}&quot;</span>, <span class='ident'>key</span>, <span class='ident'>value</span>);
}
<span class='kw'>let</span> (<span class='ident'>first_key</span>, <span class='ident'>first_value</span>) <span class='op'>=</span> <span class='ident'>map</span>.<span class='ident'>iter</span>().<span class='ident'>next</span>().<span class='ident'>unwrap</span>();
<span class='macro'>assert_eq</span><span class='macro'>!</span>((<span class='op'>*</span><span class='ident'>first_key</span>, <span class='op'>*</span><span class='ident'>first_value</span>), (<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>));</pre>
</div><h4 id='method.iter_mut' class='method'><code>fn <a href='#method.iter_mut' class='fnname'>iter_mut</a>(&amp;mut self) -&gt; <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.IterMut.html' title='bitflags::__core::collections::btree_map::IterMut'>IterMut</a>&lt;K, V&gt;</code></h4>
<div class='docblock'><p>Gets a mutable iterator over the entries of the map, sorted by key.</p>
<h1 id='examples-13' class='section-header'><a href='#examples-13'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>map</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='string'>&quot;a&quot;</span>, <span class='number'>1</span>);
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='string'>&quot;b&quot;</span>, <span class='number'>2</span>);
<span class='ident'>map</span>.<span class='ident'>insert</span>(<span class='string'>&quot;c&quot;</span>, <span class='number'>3</span>);
<span class='comment'>// add 10 to the value if the key isn&#39;t &quot;a&quot;</span>
<span class='kw'>for</span> (<span class='ident'>key</span>, <span class='ident'>value</span>) <span class='kw'>in</span> <span class='ident'>map</span>.<span class='ident'>iter_mut</span>() {
<span class='kw'>if</span> <span class='ident'>key</span> <span class='op'>!=</span> <span class='kw-2'>&amp;</span><span class='string'>&quot;a&quot;</span> {
<span class='op'>*</span><span class='ident'>value</span> <span class='op'>+=</span> <span class='number'>10</span>;
}
}</pre>
</div><h4 id='method.keys' class='method'><code>fn <a href='#method.keys' class='fnname'>keys</a>(&amp;'a self) -&gt; <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.Keys.html' title='bitflags::__core::collections::btree_map::Keys'>Keys</a>&lt;'a, K, V&gt;</code></h4>
<div class='docblock'><p>Gets an iterator over the keys of the map, in sorted order.</p>
<h1 id='examples-14' class='section-header'><a href='#examples-14'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>a</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>2</span>, <span class='string'>&quot;b&quot;</span>);
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);
<span class='kw'>let</span> <span class='ident'>keys</span>: <span class='ident'>Vec</span><span class='op'>&lt;</span>_<span class='op'>&gt;</span> <span class='op'>=</span> <span class='ident'>a</span>.<span class='ident'>keys</span>().<span class='ident'>cloned</span>().<span class='ident'>collect</span>();
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>keys</span>, [<span class='number'>1</span>, <span class='number'>2</span>]);</pre>
</div><h4 id='method.values' class='method'><code>fn <a href='#method.values' class='fnname'>values</a>(&amp;'a self) -&gt; <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.Values.html' title='bitflags::__core::collections::btree_map::Values'>Values</a>&lt;'a, K, V&gt;</code></h4>
<div class='docblock'><p>Gets an iterator over the values of the map, in order by key.</p>
<h1 id='examples-15' class='section-header'><a href='#examples-15'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>a</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;hello&quot;</span>);
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>2</span>, <span class='string'>&quot;goodbye&quot;</span>);
<span class='kw'>let</span> <span class='ident'>values</span>: <span class='ident'>Vec</span><span class='op'>&lt;</span><span class='kw-2'>&amp;</span><span class='ident'>str</span><span class='op'>&gt;</span> <span class='op'>=</span> <span class='ident'>a</span>.<span class='ident'>values</span>().<span class='ident'>cloned</span>().<span class='ident'>collect</span>();
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>values</span>, [<span class='string'>&quot;hello&quot;</span>, <span class='string'>&quot;goodbye&quot;</span>]);</pre>
</div><h4 id='method.values_mut' class='method'><code>fn <a href='#method.values_mut' class='fnname'>values_mut</a>(&amp;'a mut self) -&gt; <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.ValuesMut.html' title='bitflags::__core::collections::btree_map::ValuesMut'>ValuesMut</a>&lt;'a, K, V&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>map_values_mut</code>)<p>: recently added</p>
</em></div><div class='docblock'><p>Gets a mutable iterator over the values of the map, in order by key.</p>
<h1 id='examples-16' class='section-header'><a href='#examples-16'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>a</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='ident'>String</span>::<span class='ident'>from</span>(<span class='string'>&quot;hello&quot;</span>));
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>2</span>, <span class='ident'>String</span>::<span class='ident'>from</span>(<span class='string'>&quot;goodbye&quot;</span>));
<span class='kw'>for</span> <span class='ident'>value</span> <span class='kw'>in</span> <span class='ident'>a</span>.<span class='ident'>values_mut</span>() {
<span class='ident'>value</span>.<span class='ident'>push_str</span>(<span class='string'>&quot;!&quot;</span>);
}
<span class='kw'>let</span> <span class='ident'>values</span>: <span class='ident'>Vec</span><span class='op'>&lt;</span><span class='ident'>String</span><span class='op'>&gt;</span> <span class='op'>=</span> <span class='ident'>a</span>.<span class='ident'>values</span>().<span class='ident'>cloned</span>().<span class='ident'>collect</span>();
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>values</span>, [<span class='ident'>String</span>::<span class='ident'>from</span>(<span class='string'>&quot;hello!&quot;</span>),
<span class='ident'>String</span>::<span class='ident'>from</span>(<span class='string'>&quot;goodbye!&quot;</span>)]);</pre>
</div><h4 id='method.len' class='method'><code>fn <a href='#method.len' class='fnname'>len</a>(&amp;self) -&gt; <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.usize.html'>usize</a></code></h4>
<div class='docblock'><p>Returns the number of elements in the map.</p>
<h1 id='examples-17' class='section-header'><a href='#examples-17'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>a</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>a</span>.<span class='ident'>len</span>(), <span class='number'>0</span>);
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>a</span>.<span class='ident'>len</span>(), <span class='number'>1</span>);</pre>
</div><h4 id='method.is_empty' class='method'><code>fn <a href='#method.is_empty' class='fnname'>is_empty</a>(&amp;self) -&gt; <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.bool.html'>bool</a></code></h4>
<div class='docblock'><p>Returns true if the map contains no elements.</p>
<h1 id='examples-18' class='section-header'><a href='#examples-18'>Examples</a></h1>
<p>Basic usage:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>collections</span>::<span class='ident'>BTreeMap</span>;
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>a</span> <span class='op'>=</span> <span class='ident'>BTreeMap</span>::<span class='ident'>new</span>();
<span class='macro'>assert</span><span class='macro'>!</span>(<span class='ident'>a</span>.<span class='ident'>is_empty</span>());
<span class='ident'>a</span>.<span class='ident'>insert</span>(<span class='number'>1</span>, <span class='string'>&quot;a&quot;</span>);
<span class='macro'>assert</span><span class='macro'>!</span>(<span class='op'>!</span><span class='ident'>a</span>.<span class='ident'>is_empty</span>());</pre>
</div></div><h2 id='implementations'>Trait Implementations</h2><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/ops/trait.Drop.html' title='bitflags::__core::ops::Drop'>Drop</a> for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;</code></h3><div class='impl-items'><h4 id='method.drop' class='method'><code>fn <a href='../../../bitflags/__core/ops/trait.Drop.html#tymethod.drop' class='fnname'>drop</a>(&amp;mut self)</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/clone/trait.Clone.html' title='bitflags::__core::clone::Clone'>Clone</a> for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/clone/trait.Clone.html' title='bitflags::__core::clone::Clone'>Clone</a>, V: <a class='trait' href='../../../bitflags/__core/clone/trait.Clone.html' title='bitflags::__core::clone::Clone'>Clone</a></span></code></h3><div class='impl-items'><h4 id='method.clone' class='method'><code>fn <a href='../../../bitflags/__core/clone/trait.Clone.html#tymethod.clone' class='fnname'>clone</a>(&amp;self) -&gt; <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='method.clone_from' class='method'><code>fn <a href='../../../bitflags/__core/clone/trait.Clone.html#method.clone_from' class='fnname'>clone_from</a>(&amp;mut self, source: &amp;Self)</code></h4>
</div><h3 class='impl'><code>impl&lt;'a, K, V&gt; <a class='trait' href='../../../bitflags/__core/iter/trait.IntoIterator.html' title='bitflags::__core::iter::IntoIterator'>IntoIterator</a> for &amp;'a <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: 'a, V: 'a</span></code></h3><div class='impl-items'><h4 id='associatedtype.Item' class='type'><code>type <a href='../../../bitflags/__core/iter/trait.IntoIterator.html#associatedtype.Item' class='type'>Item</a> = <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>(</a>&amp;'a K, &amp;'a V<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>)</a></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='associatedtype.IntoIter' class='type'><code>type <a href='../../../bitflags/__core/iter/trait.IntoIterator.html#associatedtype.IntoIter' class='type'>IntoIter</a> = <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.Iter.html' title='bitflags::__core::collections::btree_map::Iter'>Iter</a>&lt;'a, K, V&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='method.into_iter' class='method'><code>fn <a href='../../../bitflags/__core/iter/trait.IntoIterator.html#tymethod.into_iter' class='fnname'>into_iter</a>(self) -&gt; <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.Iter.html' title='bitflags::__core::collections::btree_map::Iter'>Iter</a>&lt;'a, K, V&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div><h3 class='impl'><code>impl&lt;'a, K, V&gt; <a class='trait' href='../../../bitflags/__core/iter/trait.IntoIterator.html' title='bitflags::__core::iter::IntoIterator'>IntoIterator</a> for &amp;'a mut <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where V: 'a, K: 'a</span></code></h3><div class='impl-items'><h4 id='associatedtype.Item-1' class='type'><code>type <a href='../../../bitflags/__core/iter/trait.IntoIterator.html#associatedtype.Item' class='type'>Item</a> = <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>(</a>&amp;'a K, &amp;'a mut V<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>)</a></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='associatedtype.IntoIter-1' class='type'><code>type <a href='../../../bitflags/__core/iter/trait.IntoIterator.html#associatedtype.IntoIter' class='type'>IntoIter</a> = <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.IterMut.html' title='bitflags::__core::collections::btree_map::IterMut'>IterMut</a>&lt;'a, K, V&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='method.into_iter-1' class='method'><code>fn <a href='../../../bitflags/__core/iter/trait.IntoIterator.html#tymethod.into_iter' class='fnname'>into_iter</a>(self) -&gt; <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.IterMut.html' title='bitflags::__core::collections::btree_map::IterMut'>IterMut</a>&lt;'a, K, V&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/iter/trait.IntoIterator.html' title='bitflags::__core::iter::IntoIterator'>IntoIterator</a> for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;</code></h3><div class='impl-items'><h4 id='associatedtype.Item-2' class='type'><code>type <a href='../../../bitflags/__core/iter/trait.IntoIterator.html#associatedtype.Item' class='type'>Item</a> = <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>(</a>K, V<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>)</a></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='associatedtype.IntoIter-2' class='type'><code>type <a href='../../../bitflags/__core/iter/trait.IntoIterator.html#associatedtype.IntoIter' class='type'>IntoIter</a> = <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.IntoIter.html' title='bitflags::__core::collections::btree_map::IntoIter'>IntoIter</a>&lt;K, V&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='method.into_iter-2' class='method'><code>fn <a href='../../../bitflags/__core/iter/trait.IntoIterator.html#tymethod.into_iter' class='fnname'>into_iter</a>(self) -&gt; <a class='struct' href='../../../bitflags/__core/collections/btree_map/struct.IntoIter.html' title='bitflags::__core::collections::btree_map::IntoIter'>IntoIter</a>&lt;K, V&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/iter/trait.FromIterator.html' title='bitflags::__core::iter::FromIterator'>FromIterator</a>&lt;<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>(</a>K, V<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>)</a>&gt; for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a></span></code></h3><div class='impl-items'><h4 id='method.from_iter' class='method'><code>fn <a href='../../../bitflags/__core/iter/trait.FromIterator.html#tymethod.from_iter' class='fnname'>from_iter</a>&lt;T&gt;(iter: T) -&gt; <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where T: <a class='trait' href='../../../bitflags/__core/iter/trait.IntoIterator.html' title='bitflags::__core::iter::IntoIterator'>IntoIterator</a>&lt;Item=<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>(</a>K, V<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>)</a>&gt;</span></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/iter/trait.Extend.html' title='bitflags::__core::iter::Extend'>Extend</a>&lt;<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>(</a>K, V<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>)</a>&gt; for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a></span></code></h3><div class='impl-items'><h4 id='method.extend' class='method'><code>fn <a href='../../../bitflags/__core/iter/trait.Extend.html#tymethod.extend' class='fnname'>extend</a>&lt;T&gt;(&amp;mut self, iter: T) <span class='where'>where T: <a class='trait' href='../../../bitflags/__core/iter/trait.IntoIterator.html' title='bitflags::__core::iter::IntoIterator'>IntoIterator</a>&lt;Item=<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>(</a>K, V<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>)</a>&gt;</span></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div><h3 class='impl'><code>impl&lt;'a, K, V&gt; <a class='trait' href='../../../bitflags/__core/iter/trait.Extend.html' title='bitflags::__core::iter::Extend'>Extend</a>&lt;<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>(</a>&amp;'a K, &amp;'a V<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>)</a>&gt; for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/marker/trait.Copy.html' title='bitflags::__core::marker::Copy'>Copy</a> + <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a>, V: <a class='trait' href='../../../bitflags/__core/marker/trait.Copy.html' title='bitflags::__core::marker::Copy'>Copy</a></span></code></h3><div class='impl-items'><h4 id='method.extend-1' class='method'><code>fn <a href='../../../bitflags/__core/iter/trait.Extend.html#tymethod.extend' class='fnname'>extend</a>&lt;I&gt;(&amp;mut self, iter: I) <span class='where'>where I: <a class='trait' href='../../../bitflags/__core/iter/trait.IntoIterator.html' title='bitflags::__core::iter::IntoIterator'>IntoIterator</a>&lt;Item=<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>(</a>&amp;'a K, &amp;'a V<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>)</a>&gt;</span></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/hash/trait.Hash.html' title='bitflags::__core::hash::Hash'>Hash</a> for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/hash/trait.Hash.html' title='bitflags::__core::hash::Hash'>Hash</a>, V: <a class='trait' href='../../../bitflags/__core/hash/trait.Hash.html' title='bitflags::__core::hash::Hash'>Hash</a></span></code></h3><div class='impl-items'><h4 id='method.hash' class='method'><code>fn <a href='../../../bitflags/__core/hash/trait.Hash.html#tymethod.hash' class='fnname'>hash</a>&lt;H&gt;(&amp;self, state: &amp;mut H) <span class='where'>where H: <a class='trait' href='../../../bitflags/__core/hash/trait.Hasher.html' title='bitflags::__core::hash::Hasher'>Hasher</a></span></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='method.hash_slice' class='method'><code>fn <a href='../../../bitflags/__core/hash/trait.Hash.html#method.hash_slice' class='fnname'>hash_slice</a>&lt;H&gt;(data: <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.slice.html'>&amp;[Self]</a>, state: &amp;mut H) <span class='where'>where H: <a class='trait' href='../../../bitflags/__core/hash/trait.Hasher.html' title='bitflags::__core::hash::Hasher'>Hasher</a></span></code><span class="since">1.3.0</span></h4>
</div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/default/trait.Default.html' title='bitflags::__core::default::Default'>Default</a> for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a></span></code></h3><div class='impl-items'><h4 id='method.default' class='method'><code>fn <a href='../../../bitflags/__core/default/trait.Default.html#tymethod.default' class='fnname'>default</a>() -&gt; <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/cmp/trait.PartialEq.html' title='bitflags::__core::cmp::PartialEq'>PartialEq</a>&lt;<a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;&gt; for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/cmp/trait.PartialEq.html' title='bitflags::__core::cmp::PartialEq'>PartialEq</a>&lt;K&gt;, V: <a class='trait' href='../../../bitflags/__core/cmp/trait.PartialEq.html' title='bitflags::__core::cmp::PartialEq'>PartialEq</a>&lt;V&gt;</span></code></h3><div class='impl-items'><h4 id='method.eq' class='method'><code>fn <a href='../../../bitflags/__core/cmp/trait.PartialEq.html#tymethod.eq' class='fnname'>eq</a>(&amp;self, other: &amp;<a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;) -&gt; <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.bool.html'>bool</a></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='method.ne' class='method'><code>fn <a href='../../../bitflags/__core/cmp/trait.PartialEq.html#method.ne' class='fnname'>ne</a>(&amp;self, other: &amp;Rhs) -&gt; <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.bool.html'>bool</a></code></h4>
</div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/cmp/trait.Eq.html' title='bitflags::__core::cmp::Eq'>Eq</a> for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/cmp/trait.Eq.html' title='bitflags::__core::cmp::Eq'>Eq</a>, V: <a class='trait' href='../../../bitflags/__core/cmp/trait.Eq.html' title='bitflags::__core::cmp::Eq'>Eq</a></span></code></h3><div class='impl-items'></div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/cmp/trait.PartialOrd.html' title='bitflags::__core::cmp::PartialOrd'>PartialOrd</a>&lt;<a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;&gt; for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/cmp/trait.PartialOrd.html' title='bitflags::__core::cmp::PartialOrd'>PartialOrd</a>&lt;K&gt;, V: <a class='trait' href='../../../bitflags/__core/cmp/trait.PartialOrd.html' title='bitflags::__core::cmp::PartialOrd'>PartialOrd</a>&lt;V&gt;</span></code></h3><div class='impl-items'><h4 id='method.partial_cmp' class='method'><code>fn <a href='../../../bitflags/__core/cmp/trait.PartialOrd.html#tymethod.partial_cmp' class='fnname'>partial_cmp</a>(&amp;self, other: &amp;<a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;) -&gt; <a class='enum' href='../../../bitflags/__core/option/enum.Option.html' title='bitflags::__core::option::Option'>Option</a>&lt;<a class='enum' href='../../../bitflags/__core/cmp/enum.Ordering.html' title='bitflags::__core::cmp::Ordering'>Ordering</a>&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='method.lt' class='method'><code>fn <a href='../../../bitflags/__core/cmp/trait.PartialOrd.html#method.lt' class='fnname'>lt</a>(&amp;self, other: &amp;Rhs) -&gt; <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.bool.html'>bool</a></code></h4>
<h4 id='method.le' class='method'><code>fn <a href='../../../bitflags/__core/cmp/trait.PartialOrd.html#method.le' class='fnname'>le</a>(&amp;self, other: &amp;Rhs) -&gt; <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.bool.html'>bool</a></code></h4>
<h4 id='method.gt' class='method'><code>fn <a href='../../../bitflags/__core/cmp/trait.PartialOrd.html#method.gt' class='fnname'>gt</a>(&amp;self, other: &amp;Rhs) -&gt; <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.bool.html'>bool</a></code></h4>
<h4 id='method.ge' class='method'><code>fn <a href='../../../bitflags/__core/cmp/trait.PartialOrd.html#method.ge' class='fnname'>ge</a>(&amp;self, other: &amp;Rhs) -&gt; <a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.bool.html'>bool</a></code></h4>
</div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where K: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a>, V: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a></span></code></h3><div class='impl-items'><h4 id='method.cmp' class='method'><code>fn <a href='../../../bitflags/__core/cmp/trait.Ord.html#tymethod.cmp' class='fnname'>cmp</a>(&amp;self, other: &amp;<a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt;) -&gt; <a class='enum' href='../../../bitflags/__core/cmp/enum.Ordering.html' title='bitflags::__core::cmp::Ordering'>Ordering</a></code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div><h3 class='impl'><code>impl&lt;K, V&gt; <a class='trait' href='../../../bitflags/__core/fmt/trait.Debug.html' title='bitflags::__core::fmt::Debug'>Debug</a> for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where V: <a class='trait' href='../../../bitflags/__core/fmt/trait.Debug.html' title='bitflags::__core::fmt::Debug'>Debug</a>, K: <a class='trait' href='../../../bitflags/__core/fmt/trait.Debug.html' title='bitflags::__core::fmt::Debug'>Debug</a></span></code></h3><div class='impl-items'><h4 id='method.fmt' class='method'><code>fn <a href='../../../bitflags/__core/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&amp;self, f: &amp;mut <a class='struct' href='../../../bitflags/__core/fmt/struct.Formatter.html' title='bitflags::__core::fmt::Formatter'>Formatter</a>) -&gt; <a class='enum' href='../../../bitflags/__core/result/enum.Result.html' title='bitflags::__core::result::Result'>Result</a>&lt;<a class='primitive' href='https://doc.rust-lang.org/nightly/bitflags/primitive.tuple.html'>()</a>, <a class='struct' href='../../../bitflags/__core/fmt/struct.Error.html' title='bitflags::__core::fmt::Error'>Error</a>&gt;</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div><h3 class='impl'><code>impl&lt;'a, K, Q, V&gt; <a class='trait' href='../../../bitflags/__core/ops/trait.Index.html' title='bitflags::__core::ops::Index'>Index</a>&lt;&amp;'a Q&gt; for <a class='struct' href='../../../bitflags/__core/collections/struct.BTreeMap.html' title='bitflags::__core::collections::BTreeMap'>BTreeMap</a>&lt;K, V&gt; <span class='where'>where Q: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> + ?<a class='trait' href='../../../bitflags/__core/marker/trait.Sized.html' title='bitflags::__core::marker::Sized'>Sized</a>, K: <a class='trait' href='../../../bitflags/__core/cmp/trait.Ord.html' title='bitflags::__core::cmp::Ord'>Ord</a> + <a class='trait' href='../../../bitflags/__core/borrow/trait.Borrow.html' title='bitflags::__core::borrow::Borrow'>Borrow</a>&lt;Q&gt;</span></code></h3><div class='impl-items'><h4 id='associatedtype.Output' class='type'><code>type <a href='../../../bitflags/__core/ops/trait.Index.html#associatedtype.Output' class='type'>Output</a> = V</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div><h4 id='method.index' class='method'><code>fn <a href='../../../bitflags/__core/ops/trait.Index.html#tymethod.index' class='fnname'>index</a>(&amp;self, key: &amp;Q) -&gt; &amp;V</code></h4>
<div class='stability'><em class='stab unstable'>Unstable (<code>collections</code>)<p>: library is unlikely to be stabilized with the current layout and name, use std::collections instead</p>
</em></div></div></section>
<section id='search' class="content hidden"></section>
<section class="footer"></section>
<aside id="help" class="hidden">
<div>
<h1 class="hidden">Help</h1>
<div class="shortcuts">
<h2>Keyboard Shortcuts</h2>
<dl>
<dt>?</dt>
<dd>Show this help dialog</dd>
<dt>S</dt>
<dd>Focus the search field</dd>
<dt>&larrb;</dt>
<dd>Move up in search results</dd>
<dt>&rarrb;</dt>
<dd>Move down in search results</dd>
<dt>&#9166;</dt>
<dd>Go to active search result</dd>
</dl>
</div>
<div class="infos">
<h2>Search Tricks</h2>
<p>
Prefix searches with a type followed by a colon (e.g.
<code>fn:</code>) to restrict the search to a given type.
</p>
<p>
Accepted types are: <code>fn</code>, <code>mod</code>,
<code>struct</code>, <code>enum</code>,
<code>trait</code>, <code>type</code>, <code>macro</code>,
and <code>const</code>.
</p>
<p>
Search functions by type signature (e.g.
<code>vec -> usize</code> or <code>* -> vec</code>)
</p>
</div>
</div>
</aside>
<script>
window.rootPath = "../../../";
window.currentCrate = "bitflags";
window.playgroundUrl = "";
</script>
<script src="../../../jquery.js"></script>
<script src="../../../main.js"></script>
<script defer src="../../../search-index.js"></script>
</body>
</html>
Reference in a new issue View git blame Copy permalink