<!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 `BufWriter` struct in crate `std`."><meta name="keywords" content="rust, rustlang, rust-lang, BufWriter"><title>std::io::BufWriter - Rust</title><link rel="stylesheet" type="text/css" href="../../normalize1.35.0.css"><link rel="stylesheet" type="text/css" href="../../rustdoc1.35.0.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../../dark1.35.0.css"><link rel="stylesheet" type="text/css" href="../../light1.35.0.css" id="themeStyle"><script src="../../storage1.35.0.js"></script><noscript><link rel="stylesheet" href="../../noscript1.35.0.css"></noscript><link rel="shortcut icon" href="../../favicon1.35.0.ico"><style type="text/css">#crate-search{background-image:url("../../down-arrow1.35.0.svg");}</style></head><body class="rustdoc struct"><!--[if lte IE 8]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="sidebar-menu">☰</div><a href='../../std/index.html'><img src='../../rust-logo1.35.0.png' alt='logo' width='100'></a><p class='location'>Struct BufWriter</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#methods">Methods</a><div class="sidebar-links"><a href="#method.buffer">buffer</a><a href="#method.get_mut">get_mut</a><a href="#method.get_ref">get_ref</a><a href="#method.into_inner">into_inner</a><a href="#method.new">new</a><a href="#method.with_capacity">with_capacity</a></div><a class="sidebar-title" href="#implementations">Trait Implementations</a><div class="sidebar-links"><a href="#impl-Debug">Debug</a><a href="#impl-Drop">Drop</a><a href="#impl-Seek">Seek</a><a href="#impl-Write">Write</a></div><a class="sidebar-title" href="#synthetic-implementations">Auto Trait Implementations</a><div class="sidebar-links"><a href="#impl-Send">Send</a><a href="#impl-Sync">Sync</a></div><a class="sidebar-title" href="#blanket-implementations">Blanket Implementations</a><div class="sidebar-links"><a href="#impl-Any">Any</a><a href="#impl-Borrow">Borrow</a><a href="#impl-BorrowMut">BorrowMut</a><a href="#impl-From">From</a><a href="#impl-Into">Into</a><a href="#impl-TryFrom">TryFrom</a><a href="#impl-TryInto">TryInto</a></div></div><p class='location'><a href='../index.html'>std</a>::<wbr><a href='index.html'>io</a></p><script>window.sidebarCurrent = {name: 'BufWriter', ty: 'struct', relpath: ''};</script><script defer src="sidebar-items.js"></script></div></nav><div class="theme-picker"><button id="theme-picker" aria-label="Pick another theme!"><img src="../../brush1.35.0.svg" width="18" alt="Pick another theme!"></button><div id="theme-choices"></div></div><script src="../../theme1.35.0.js"></script><nav class="sub"><form class="search-form js-only"><div class="search-container"><div><select id="crate-search"><option value="All crates">All crates</option></select><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"></div><a id="settings-menu" href="../../settings.html"><img src="../../wheel1.35.0.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><h1 class='fqn'><span class='out-of-band'><span class='since' title='Stable since Rust version 1.0.0'>1.0.0</span><span id='render-detail'><a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class='inner'>−</span>]</a></span><a class='srclink' href='../../src/std/io/buffered.rs.html#412-419' title='goto source code'>[src]</a></span><span class='in-band'>Struct <a href='../index.html'>std</a>::<wbr><a href='index.html'>io</a>::<wbr><a class="struct" href=''>BufWriter</a></span></h1><div class="docblock type-decl hidden-by-usual-hider"><pre class='rust struct'>pub struct BufWriter<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a>> { /* fields omitted */ }</pre></div><div class='docblock'><p>Wraps a writer and buffers its output.</p>
<p>It can be excessively inefficient to work directly with something that
implements <a href="../../std/io/trait.Write.html"><code>Write</code></a>. For example, every call to
<a href="../../std/net/struct.TcpStream.html#method.write"><code>write</code></a> on <a href="../../std/net/struct.TcpStream.html"><code>TcpStream</code></a> results in a system call. A
<code>BufWriter</code> keeps an in-memory buffer of data and writes it to an underlying
writer in large, infrequent batches.</p>
<p><code>BufWriter</code> can improve the speed of programs that make <em>small</em> and
<em>repeated</em> write calls to the same file or network socket. It does not
help when writing very large amounts at once, or writing just one or a few
times. It also provides no advantage when writing to a destination that is
in memory, like a <code>Vec<u8></code>.</p>
<p>When the <code>BufWriter</code> is dropped, the contents of its buffer will be written
out. However, any errors that happen in the process of flushing the buffer
when the writer is dropped will be ignored. Code that wishes to handle such
errors must manually call <a href="#method.flush"><code>flush</code></a> before the writer is dropped.</p>
<h1 id="examples" class="section-header"><a href="#examples">Examples</a></h1>
<p>Let's write the numbers one through ten to a <a href="../../std/net/struct.TcpStream.html"><code>TcpStream</code></a>:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">io</span>::<span class="ident">prelude</span>::<span class="kw-2">*</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">net</span>::<span class="ident">TcpStream</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">stream</span> <span class="op">=</span> <span class="ident">TcpStream</span>::<span class="ident">connect</span>(<span class="string">"127.0.0.1:34254"</span>).<span class="ident">unwrap</span>();
<span class="kw">for</span> <span class="ident">i</span> <span class="kw">in</span> <span class="number">0</span>..<span class="number">10</span> {
<span class="ident">stream</span>.<span class="ident">write</span>(<span class="kw-2">&</span>[<span class="ident">i</span><span class="op">+</span><span class="number">1</span>]).<span class="ident">unwrap</span>();
}<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Aio%3A%3Aprelude%3A%3A*%3B%0Ause%20std%3A%3Anet%3A%3ATcpStream%3B%0A%0Alet%20mut%20stream%20%3D%20TcpStream%3A%3Aconnect(%22127.0.0.1%3A34254%22).unwrap()%3B%0A%0Afor%20i%20in%200..10%20%7B%0A%20%20%20%20stream.write(%26%5Bi%2B1%5D).unwrap()%3B%0A%7D%0A%7D">Run</a></pre></div>
<p>Because we're not buffering, we write each one in turn, incurring the
overhead of a system call per byte written. We can fix this with a
<code>BufWriter</code>:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">io</span>::<span class="ident">prelude</span>::<span class="kw-2">*</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">io</span>::<span class="ident">BufWriter</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">net</span>::<span class="ident">TcpStream</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">stream</span> <span class="op">=</span> <span class="ident">BufWriter</span>::<span class="ident">new</span>(<span class="ident">TcpStream</span>::<span class="ident">connect</span>(<span class="string">"127.0.0.1:34254"</span>).<span class="ident">unwrap</span>());
<span class="kw">for</span> <span class="ident">i</span> <span class="kw">in</span> <span class="number">0</span>..<span class="number">10</span> {
<span class="ident">stream</span>.<span class="ident">write</span>(<span class="kw-2">&</span>[<span class="ident">i</span><span class="op">+</span><span class="number">1</span>]).<span class="ident">unwrap</span>();
}<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Aio%3A%3Aprelude%3A%3A*%3B%0Ause%20std%3A%3Aio%3A%3ABufWriter%3B%0Ause%20std%3A%3Anet%3A%3ATcpStream%3B%0A%0Alet%20mut%20stream%20%3D%20BufWriter%3A%3Anew(TcpStream%3A%3Aconnect(%22127.0.0.1%3A34254%22).unwrap())%3B%0A%0Afor%20i%20in%200..10%20%7B%0A%20%20%20%20stream.write(%26%5Bi%2B1%5D).unwrap()%3B%0A%7D%0A%7D">Run</a></pre></div>
<p>By wrapping the stream with a <code>BufWriter</code>, these ten writes are all grouped
together by the buffer, and will all be written out in one system call when
the <code>stream</code> is dropped.</p>
</div><h2 id='methods' class='small-section-header'>Methods<a href='#methods' class='anchor'></a></h2><h3 id='impl' class='impl'><code class='in-band'>impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a>> <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></code><a href='#impl' class='anchor'></a><a class='srclink' href='../../src/std/io/buffered.rs.html#449-594' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.new' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></span></div><div class="content hidden"><h3 class="important">Important traits for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></h3><code class="content"><span class="where fmt-newline">impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a>> <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></span></code></div></div><code id='new.v'>pub fn <a href='#method.new' class='fnname'>new</a>(inner: W) -> <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></code><a class='srclink' href='../../src/std/io/buffered.rs.html#462-464' title='goto source code'>[src]</a></h4><div class='docblock'><p>Creates a new <code>BufWriter</code> with a default buffer capacity. The default is currently 8 KB,
but may change in the future.</p>
<h1 id="examples-1" class="section-header"><a href="#examples-1">Examples</a></h1>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">io</span>::<span class="ident">BufWriter</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">net</span>::<span class="ident">TcpStream</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">buffer</span> <span class="op">=</span> <span class="ident">BufWriter</span>::<span class="ident">new</span>(<span class="ident">TcpStream</span>::<span class="ident">connect</span>(<span class="string">"127.0.0.1:34254"</span>).<span class="ident">unwrap</span>());<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Aio%3A%3ABufWriter%3B%0Ause%20std%3A%3Anet%3A%3ATcpStream%3B%0A%0Alet%20mut%20buffer%20%3D%20BufWriter%3A%3Anew(TcpStream%3A%3Aconnect(%22127.0.0.1%3A34254%22).unwrap())%3B%0A%7D">Run</a></pre></div>
</div><h4 id='method.with_capacity' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></span></div><div class="content hidden"><h3 class="important">Important traits for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></h3><code class="content"><span class="where fmt-newline">impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a>> <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></span></code></div></div><code id='with_capacity.v'>pub fn <a href='#method.with_capacity' class='fnname'>with_capacity</a>(cap: <a class="primitive" href="../primitive.usize.html">usize</a>, inner: W) -> <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></code><a class='srclink' href='../../src/std/io/buffered.rs.html#480-486' title='goto source code'>[src]</a></h4><div class='docblock'><p>Creates a new <code>BufWriter</code> with the specified buffer capacity.</p>
<h1 id="examples-2" class="section-header"><a href="#examples-2">Examples</a></h1>
<p>Creating a buffer with a buffer of a hundred bytes.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">io</span>::<span class="ident">BufWriter</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">net</span>::<span class="ident">TcpStream</span>;
<span class="kw">let</span> <span class="ident">stream</span> <span class="op">=</span> <span class="ident">TcpStream</span>::<span class="ident">connect</span>(<span class="string">"127.0.0.1:34254"</span>).<span class="ident">unwrap</span>();
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">buffer</span> <span class="op">=</span> <span class="ident">BufWriter</span>::<span class="ident">with_capacity</span>(<span class="number">100</span>, <span class="ident">stream</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Aio%3A%3ABufWriter%3B%0Ause%20std%3A%3Anet%3A%3ATcpStream%3B%0A%0Alet%20stream%20%3D%20TcpStream%3A%3Aconnect(%22127.0.0.1%3A34254%22).unwrap()%3B%0Alet%20mut%20buffer%20%3D%20BufWriter%3A%3Awith_capacity(100%2C%20stream)%3B%0A%7D">Run</a></pre></div>
</div><h4 id='method.get_ref' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F</h3><code class="content"><span class="where fmt-newline">impl<'_, F> <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F <span class="where fmt-newline">where<br> F: <a class="trait" href="../../std/marker/trait.Unpin.html" title="trait std::marker::Unpin">Unpin</a> + <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../std/future/trait.Future.html#associatedtype.Output' class="type">Output</a> = <F as <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a>>::<a class="type" href="../../std/future/trait.Future.html#associatedtype.Output" title="type std::future::Future::Output">Output</a>;</span><span class="where fmt-newline">impl<'_, I> <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>I <span class="where fmt-newline">where<br> I: <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../std/iter/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = <I as <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a>>::<a class="type" href="../../std/iter/trait.Iterator.html#associatedtype.Item" title="type std::iter::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl<R: <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, '_> <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>R</span><span class="where fmt-newline">impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, '_> <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>W</span></code></div></div><code id='get_ref.v'>pub fn <a href='#method.get_ref' class='fnname'>get_ref</a>(&self) -> <a class="primitive" href="../primitive.reference.html">&</a>W</code><a class='srclink' href='../../src/std/io/buffered.rs.html#529' title='goto source code'>[src]</a></h4><div class='docblock'><p>Gets a reference to the underlying writer.</p>
<h1 id="examples-3" class="section-header"><a href="#examples-3">Examples</a></h1>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">io</span>::<span class="ident">BufWriter</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">net</span>::<span class="ident">TcpStream</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">buffer</span> <span class="op">=</span> <span class="ident">BufWriter</span>::<span class="ident">new</span>(<span class="ident">TcpStream</span>::<span class="ident">connect</span>(<span class="string">"127.0.0.1:34254"</span>).<span class="ident">unwrap</span>());
<span class="comment">// we can use reference just like buffer</span>
<span class="kw">let</span> <span class="ident">reference</span> <span class="op">=</span> <span class="ident">buffer</span>.<span class="ident">get_ref</span>();<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Aio%3A%3ABufWriter%3B%0Ause%20std%3A%3Anet%3A%3ATcpStream%3B%0A%0Alet%20mut%20buffer%20%3D%20BufWriter%3A%3Anew(TcpStream%3A%3Aconnect(%22127.0.0.1%3A34254%22).unwrap())%3B%0A%0A%2F%2F%20we%20can%20use%20reference%20just%20like%20buffer%0Alet%20reference%20%3D%20buffer.get_ref()%3B%0A%7D">Run</a></pre></div>
</div><h4 id='method.get_mut' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F</h3><code class="content"><span class="where fmt-newline">impl<'_, F> <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F <span class="where fmt-newline">where<br> F: <a class="trait" href="../../std/marker/trait.Unpin.html" title="trait std::marker::Unpin">Unpin</a> + <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../std/future/trait.Future.html#associatedtype.Output' class="type">Output</a> = <F as <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a>>::<a class="type" href="../../std/future/trait.Future.html#associatedtype.Output" title="type std::future::Future::Output">Output</a>;</span><span class="where fmt-newline">impl<'_, I> <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>I <span class="where fmt-newline">where<br> I: <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../std/iter/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = <I as <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a>>::<a class="type" href="../../std/iter/trait.Iterator.html#associatedtype.Item" title="type std::iter::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl<R: <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, '_> <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>R</span><span class="where fmt-newline">impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, '_> <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>W</span></code></div></div><code id='get_mut.v'>pub fn <a href='#method.get_mut' class='fnname'>get_mut</a>(&mut self) -> <a class="primitive" href="../primitive.reference.html">&mut </a>W</code><a class='srclink' href='../../src/std/io/buffered.rs.html#547' title='goto source code'>[src]</a></h4><div class='docblock'><p>Gets a mutable reference to the underlying writer.</p>
<p>It is inadvisable to directly write to the underlying writer.</p>
<h1 id="examples-4" class="section-header"><a href="#examples-4">Examples</a></h1>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">io</span>::<span class="ident">BufWriter</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">net</span>::<span class="ident">TcpStream</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">buffer</span> <span class="op">=</span> <span class="ident">BufWriter</span>::<span class="ident">new</span>(<span class="ident">TcpStream</span>::<span class="ident">connect</span>(<span class="string">"127.0.0.1:34254"</span>).<span class="ident">unwrap</span>());
<span class="comment">// we can use reference just like buffer</span>
<span class="kw">let</span> <span class="ident">reference</span> <span class="op">=</span> <span class="ident">buffer</span>.<span class="ident">get_mut</span>();<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Aio%3A%3ABufWriter%3B%0Ause%20std%3A%3Anet%3A%3ATcpStream%3B%0A%0Alet%20mut%20buffer%20%3D%20BufWriter%3A%3Anew(TcpStream%3A%3Aconnect(%22127.0.0.1%3A34254%22).unwrap())%3B%0A%0A%2F%2F%20we%20can%20use%20reference%20just%20like%20buffer%0Alet%20reference%20%3D%20buffer.get_mut()%3B%0A%7D">Run</a></pre></div>
</div><h4 id='method.buffer' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="primitive" href="../primitive.slice.html">&'_ [</a><a class="primitive" href="../primitive.u8.html">u8</a><a class="primitive" href="../primitive.slice.html">]</a></span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="../primitive.slice.html">&'_ [</a><a class="primitive" href="../primitive.u8.html">u8</a><a class="primitive" href="../primitive.slice.html">]</a></h3><code class="content"><span class="where fmt-newline">impl<'_> <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="../primitive.slice.html">&'_ [</a><a class="primitive" href="../primitive.u8.html">u8</a><a class="primitive" href="../primitive.slice.html">]</a></span><span class="where fmt-newline">impl<'_> <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="../primitive.slice.html">&'_ mut [</a><a class="primitive" href="../primitive.u8.html">u8</a><a class="primitive" href="../primitive.slice.html">]</a></span></code></div></div><code id='buffer.v'>pub fn <a href='#method.buffer' class='fnname'>buffer</a>(&self) -> <a class="primitive" href="../primitive.slice.html">&[</a><a class="primitive" href="../primitive.u8.html">u8</a><a class="primitive" href="../primitive.slice.html">]</a></code><a class='srclink' href='../../src/std/io/buffered.rs.html#564-566' title='goto source code'>[src]</a></h4><div class='stability'><div class='stab unstable'><span class='emoji'>🔬</span> This is a nightly-only experimental API. (<code>bufreader_buffer</code> <a href="https://github.com/rust-lang/rust/issues/45323">#45323</a>)</div></div><div class='docblock'><p>Returns a reference to the internally buffered data.</p>
<h1 id="examples-5" class="section-header"><a href="#examples-5">Examples</a></h1>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">io</span>::<span class="ident">BufWriter</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">net</span>::<span class="ident">TcpStream</span>;
<span class="kw">let</span> <span class="ident">buf_writer</span> <span class="op">=</span> <span class="ident">BufWriter</span>::<span class="ident">new</span>(<span class="ident">TcpStream</span>::<span class="ident">connect</span>(<span class="string">"127.0.0.1:34254"</span>).<span class="ident">unwrap</span>());
<span class="comment">// See how many bytes are currently buffered</span>
<span class="kw">let</span> <span class="ident">bytes_buffered</span> <span class="op">=</span> <span class="ident">buf_writer</span>.<span class="ident">buffer</span>().<span class="ident">len</span>();<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0A%23!%5Bfeature(bufreader_buffer)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Aio%3A%3ABufWriter%3B%0Ause%20std%3A%3Anet%3A%3ATcpStream%3B%0A%0Alet%20buf_writer%20%3D%20BufWriter%3A%3Anew(TcpStream%3A%3Aconnect(%22127.0.0.1%3A34254%22).unwrap())%3B%0A%0A%2F%2F%20See%20how%20many%20bytes%20are%20currently%20buffered%0Alet%20bytes_buffered%20%3D%20buf_writer.buffer().len()%3B%0A%7D&version=nightly">Run</a></pre></div>
</div><h4 id='method.into_inner' class="method"><code id='into_inner.v'>pub fn <a href='#method.into_inner' class='fnname'>into_inner</a>(self) -> <a class="enum" href="../../std/result/enum.Result.html" title="enum std::result::Result">Result</a><W, <a class="struct" href="../../std/io/struct.IntoInnerError.html" title="struct std::io::IntoInnerError">IntoInnerError</a><<a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W>>></code><a class='srclink' href='../../src/std/io/buffered.rs.html#588-593' title='goto source code'>[src]</a></h4><div class='docblock'><p>Unwraps this <code>BufWriter</code>, returning the underlying writer.</p>
<p>The buffer is written out before returning the writer.</p>
<h1 id="errors" class="section-header"><a href="#errors">Errors</a></h1>
<p>An <code>Err</code> will be returned if an error occurs while flushing the buffer.</p>
<h1 id="examples-6" class="section-header"><a href="#examples-6">Examples</a></h1>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">io</span>::<span class="ident">BufWriter</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">net</span>::<span class="ident">TcpStream</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">buffer</span> <span class="op">=</span> <span class="ident">BufWriter</span>::<span class="ident">new</span>(<span class="ident">TcpStream</span>::<span class="ident">connect</span>(<span class="string">"127.0.0.1:34254"</span>).<span class="ident">unwrap</span>());
<span class="comment">// unwrap the TcpStream and flush the buffer</span>
<span class="kw">let</span> <span class="ident">stream</span> <span class="op">=</span> <span class="ident">buffer</span>.<span class="ident">into_inner</span>().<span class="ident">unwrap</span>();<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Aio%3A%3ABufWriter%3B%0Ause%20std%3A%3Anet%3A%3ATcpStream%3B%0A%0Alet%20mut%20buffer%20%3D%20BufWriter%3A%3Anew(TcpStream%3A%3Aconnect(%22127.0.0.1%3A34254%22).unwrap())%3B%0A%0A%2F%2F%20unwrap%20the%20TcpStream%20and%20flush%20the%20buffer%0Alet%20stream%20%3D%20buffer.into_inner().unwrap()%3B%0A%7D">Run</a></pre></div>
</div></div><h2 id='implementations' class='small-section-header'>Trait Implementations<a href='#implementations' class='anchor'></a></h2><div id='implementations-list'><h3 id='impl-Write' class='impl'><code class='in-band'>impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a>> <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></code><a href='#impl-Write' class='anchor'></a><a class='srclink' href='../../src/std/io/buffered.rs.html#597-630' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.write' class="method hidden"><code id='write.v'>fn <a href='../../std/io/trait.Write.html#tymethod.write' class='fnname'>write</a>(&mut self, buf: <a class="primitive" href="../primitive.slice.html">&[</a><a class="primitive" href="../primitive.u8.html">u8</a><a class="primitive" href="../primitive.slice.html">]</a>) -> <a class="type" href="../../std/io/type.Result.html" title="type std::io::Result">Result</a><<a class="primitive" href="../primitive.usize.html">usize</a>></code><a class='srclink' href='../../src/std/io/buffered.rs.html#598-610' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Write a buffer into this writer, returning how many bytes were written. <a href="../../std/io/trait.Write.html#tymethod.write">Read more</a></p>
</div><h4 id='method.write_vectored' class="method hidden"><code id='write_vectored.v'>fn <a href='../../std/io/trait.Write.html#method.write_vectored' class='fnname'>write_vectored</a>(&mut self, bufs: <a class="primitive" href="../primitive.slice.html">&[</a><a class="struct" href="../../std/io/struct.IoVec.html" title="struct std::io::IoVec">IoVec</a><a class="primitive" href="../primitive.slice.html">]</a>) -> <a class="type" href="../../std/io/type.Result.html" title="type std::io::Result">Result</a><<a class="primitive" href="../primitive.usize.html">usize</a>></code><a class='srclink' href='../../src/std/io/buffered.rs.html#612-625' title='goto source code'>[src]</a></h4><div class='stability hidden'><div class='stab unstable'><span class='emoji'>🔬</span> This is a nightly-only experimental API. (<code>iovec</code> <a href="https://github.com/rust-lang/rust/issues/58452">#58452</a>)</div></div><div class='docblock hidden'><p>Like <code>write</code>, except that it writes from a slice of buffers. <a href="../../std/io/trait.Write.html#method.write_vectored">Read more</a></p>
</div><h4 id='method.flush' class="method hidden"><code id='flush.v'>fn <a href='../../std/io/trait.Write.html#tymethod.flush' class='fnname'>flush</a>(&mut self) -> <a class="type" href="../../std/io/type.Result.html" title="type std::io::Result">Result</a><<a class="primitive" href="../primitive.unit.html">()</a>></code><a class='srclink' href='../../src/std/io/buffered.rs.html#627-629' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Flush this output stream, ensuring that all intermediately buffered contents reach their destination. <a href="../../std/io/trait.Write.html#tymethod.flush">Read more</a></p>
</div><h4 id='method.write_all' class="method"><code id='write_all.v'>fn <a href='../../std/io/trait.Write.html#method.write_all' class='fnname'>write_all</a>(&mut self, buf: <a class="primitive" href="../primitive.slice.html">&[</a><a class="primitive" href="../primitive.u8.html">u8</a><a class="primitive" href="../primitive.slice.html">]</a>) -> <a class="type" href="../../std/io/type.Result.html" title="type std::io::Result">Result</a><<a class="primitive" href="../primitive.unit.html">()</a>></code><a class='srclink' href='../../src/std/io/mod.rs.html#1206-1217' title='goto source code'>[src]</a></h4><div class='docblock'><p>Attempts to write an entire buffer into this writer. <a href="../../std/io/trait.Write.html#method.write_all">Read more</a></p>
</div><h4 id='method.write_fmt' class="method"><code id='write_fmt.v'>fn <a href='../../std/io/trait.Write.html#method.write_fmt' class='fnname'>write_fmt</a>(&mut self, fmt: <a class="struct" href="../../std/fmt/struct.Arguments.html" title="struct std::fmt::Arguments">Arguments</a>) -> <a class="type" href="../../std/io/type.Result.html" title="type std::io::Result">Result</a><<a class="primitive" href="../primitive.unit.html">()</a>></code><a class='srclink' href='../../src/std/io/mod.rs.html#1258-1290' title='goto source code'>[src]</a></h4><div class='docblock'><p>Writes a formatted string into this writer, returning any error encountered. <a href="../../std/io/trait.Write.html#method.write_fmt">Read more</a></p>
</div><h4 id='method.by_ref' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F</h3><code class="content"><span class="where fmt-newline">impl<'_, F> <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F <span class="where fmt-newline">where<br> F: <a class="trait" href="../../std/marker/trait.Unpin.html" title="trait std::marker::Unpin">Unpin</a> + <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../std/future/trait.Future.html#associatedtype.Output' class="type">Output</a> = <F as <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a>>::<a class="type" href="../../std/future/trait.Future.html#associatedtype.Output" title="type std::future::Future::Output">Output</a>;</span><span class="where fmt-newline">impl<'_, I> <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>I <span class="where fmt-newline">where<br> I: <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../std/iter/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = <I as <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a>>::<a class="type" href="../../std/iter/trait.Iterator.html#associatedtype.Item" title="type std::iter::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl<R: <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, '_> <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>R</span><span class="where fmt-newline">impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, '_> <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>W</span></code></div></div><code id='by_ref.v'>fn <a href='../../std/io/trait.Write.html#method.by_ref' class='fnname'>by_ref</a>(&mut self) -> <a class="primitive" href="../primitive.reference.html">&mut </a>Self <span class="where fmt-newline">where<br> Self: <a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></code><a class='srclink' href='../../src/std/io/mod.rs.html#1314' title='goto source code'>[src]</a></h4><div class='docblock'><p>Creates a "by reference" adaptor for this instance of <code>Write</code>. <a href="../../std/io/trait.Write.html#method.by_ref">Read more</a></p>
</div></div><h3 id='impl-Seek' class='impl'><code class='in-band'>impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> + <a class="trait" href="../../std/io/trait.Seek.html" title="trait std::io::Seek">Seek</a>> <a class="trait" href="../../std/io/trait.Seek.html" title="trait std::io::Seek">Seek</a> for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></code><a href='#impl-Seek' class='anchor'></a><a class='srclink' href='../../src/std/io/buffered.rs.html#643-650' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.seek' class="method"><code id='seek.v'>fn <a href='../../std/io/trait.Seek.html#tymethod.seek' class='fnname'>seek</a>(&mut self, pos: <a class="enum" href="../../std/io/enum.SeekFrom.html" title="enum std::io::SeekFrom">SeekFrom</a>) -> <a class="type" href="../../std/io/type.Result.html" title="type std::io::Result">Result</a><<a class="primitive" href="../primitive.u64.html">u64</a>></code><a class='srclink' href='../../src/std/io/buffered.rs.html#647-649' title='goto source code'>[src]</a></h4><div class='docblock'><p>Seek to the offset, in bytes, in the underlying writer.</p>
<p>Seeking always writes out the internal buffer before seeking.</p>
</div><h4 id='method.stream_len' class="method"><code id='stream_len.v'>fn <a href='../../std/io/trait.Seek.html#method.stream_len' class='fnname'>stream_len</a>(&mut self) -> <a class="type" href="../../std/io/type.Result.html" title="type std::io::Result">Result</a><<a class="primitive" href="../primitive.u64.html">u64</a>></code><a class='srclink' href='../../src/std/io/mod.rs.html#1398-1409' title='goto source code'>[src]</a></h4><div class='stability'><div class='stab unstable'><span class='emoji'>🔬</span> This is a nightly-only experimental API. (<code>seek_convenience</code> <a href="https://github.com/rust-lang/rust/issues/59359">#59359</a>)</div></div><div class='docblock'><p>Returns the length of this stream (in bytes). <a href="../../std/io/trait.Seek.html#method.stream_len">Read more</a></p>
</div><h4 id='method.stream_position' class="method"><code id='stream_position.v'>fn <a href='../../std/io/trait.Seek.html#method.stream_position' class='fnname'>stream_position</a>(&mut self) -> <a class="type" href="../../std/io/type.Result.html" title="type std::io::Result">Result</a><<a class="primitive" href="../primitive.u64.html">u64</a>></code><a class='srclink' href='../../src/std/io/mod.rs.html#1437-1439' title='goto source code'>[src]</a></h4><div class='stability'><div class='stab unstable'><span class='emoji'>🔬</span> This is a nightly-only experimental API. (<code>seek_convenience</code> <a href="https://github.com/rust-lang/rust/issues/59359">#59359</a>)</div></div><div class='docblock'><p>Returns the current seek position from the start of the stream. <a href="../../std/io/trait.Seek.html#method.stream_position">Read more</a></p>
</div></div><h3 id='impl-Debug' class='impl'><code class='in-band'>impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a>> <a class="trait" href="../../std/fmt/trait.Debug.html" title="trait std::fmt::Debug">Debug</a> for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W> <span class="where fmt-newline">where<br> W: <a class="trait" href="../../std/fmt/trait.Debug.html" title="trait std::fmt::Debug">Debug</a>, </span></code><a href='#impl-Debug' class='anchor'></a><a class='srclink' href='../../src/std/io/buffered.rs.html#633-640' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.fmt' class="method hidden"><code id='fmt.v'>fn <a href='../../std/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&self, fmt: &mut <a class="struct" href="../../std/fmt/struct.Formatter.html" title="struct std::fmt::Formatter">Formatter</a>) -> <a class="type" href="../../std/fmt/type.Result.html" title="type std::fmt::Result">Result</a></code><a class='srclink' href='../../src/std/io/buffered.rs.html#634-639' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Formats the value using the given formatter. <a href="../../std/fmt/trait.Debug.html#tymethod.fmt">Read more</a></p>
</div></div><h3 id='impl-Drop' class='impl'><code class='in-band'>impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a>> <a class="trait" href="../../std/ops/trait.Drop.html" title="trait std::ops::Drop">Drop</a> for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W></code><a href='#impl-Drop' class='anchor'></a><a class='srclink' href='../../src/std/io/buffered.rs.html#653-660' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.drop' class="method hidden"><code id='drop.v'>fn <a href='../../std/ops/trait.Drop.html#tymethod.drop' class='fnname'>drop</a>(&mut self)</code><a class='srclink' href='../../src/std/io/buffered.rs.html#654-659' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Executes the destructor for this type. <a href="../../std/ops/trait.Drop.html#tymethod.drop">Read more</a></p>
</div></div></div><h2 id='synthetic-implementations' class='small-section-header'>Auto Trait Implementations<a href='#synthetic-implementations' class='anchor'></a></h2><div id='synthetic-implementations-list'><h3 id='impl-Send' class='impl'><code class='in-band'>impl<W> <a class="trait" href="../../std/marker/trait.Send.html" title="trait std::marker::Send">Send</a> for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W> <span class="where fmt-newline">where<br> W: <a class="trait" href="../../std/marker/trait.Send.html" title="trait std::marker::Send">Send</a>, </span></code><a href='#impl-Send' class='anchor'></a></h3><div class='impl-items'></div><h3 id='impl-Sync' class='impl'><code class='in-band'>impl<W> <a class="trait" href="../../std/marker/trait.Sync.html" title="trait std::marker::Sync">Sync</a> for <a class="struct" href="../../std/io/struct.BufWriter.html" title="struct std::io::BufWriter">BufWriter</a><W> <span class="where fmt-newline">where<br> W: <a class="trait" href="../../std/marker/trait.Sync.html" title="trait std::marker::Sync">Sync</a>, </span></code><a href='#impl-Sync' class='anchor'></a></h3><div class='impl-items'></div></div><h2 id='blanket-implementations' class='small-section-header'>Blanket Implementations<a href='#blanket-implementations' class='anchor'></a></h2><div id='blanket-implementations-list'><h3 id='impl-TryFrom' class='impl'><code class='in-band'>impl<T, U> <a class="trait" href="../../std/convert/trait.TryFrom.html" title="trait std::convert::TryFrom">TryFrom</a> for T <span class="where fmt-newline">where<br> U: <a class="trait" href="../../std/convert/trait.Into.html" title="trait std::convert::Into">Into</a><T>, </span></code><a href='#impl-TryFrom' class='anchor'></a><a class='srclink' href='../../src/core/convert.rs.html#565-571' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='associatedtype.Error' class="type"><code id='Error.t'>type <a href='../../std/convert/trait.TryFrom.html#associatedtype.Error' class="type">Error</a> = <a class="enum" href="../../std/convert/enum.Infallible.html" title="enum std::convert::Infallible">Infallible</a></code></h4><div class='docblock'><p>The type returned in the event of a conversion error.</p>
</div><h4 id='method.try_from' class="method hidden"><code id='try_from.v'>fn <a href='../../std/convert/trait.TryFrom.html#tymethod.try_from' class='fnname'>try_from</a>(value: U) -> <a class="enum" href="../../std/result/enum.Result.html" title="enum std::result::Result">Result</a><T, <T as <a class="trait" href="../../std/convert/trait.TryFrom.html" title="trait std::convert::TryFrom">TryFrom</a><U>>::<a class="type" href="../../std/convert/trait.TryFrom.html#associatedtype.Error" title="type std::convert::TryFrom::Error">Error</a>></code><a class='srclink' href='../../src/core/convert.rs.html#568-570' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Performs the conversion.</p>
</div></div><h3 id='impl-From' class='impl'><code class='in-band'>impl<T> <a class="trait" href="../../std/convert/trait.From.html" title="trait std::convert::From">From</a> for T</code><a href='#impl-From' class='anchor'></a><a class='srclink' href='../../src/core/convert.rs.html#546-548' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.from' class="method hidden"><code id='from.v'>fn <a href='../../std/convert/trait.From.html#tymethod.from' class='fnname'>from</a>(t: T) -> T</code><a class='srclink' href='../../src/core/convert.rs.html#547' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Performs the conversion.</p>
</div></div><h3 id='impl-TryInto' class='impl'><code class='in-band'>impl<T, U> <a class="trait" href="../../std/convert/trait.TryInto.html" title="trait std::convert::TryInto">TryInto</a> for T <span class="where fmt-newline">where<br> U: <a class="trait" href="../../std/convert/trait.TryFrom.html" title="trait std::convert::TryFrom">TryFrom</a><T>, </span></code><a href='#impl-TryInto' class='anchor'></a><a class='srclink' href='../../src/core/convert.rs.html#553-560' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='associatedtype.Error-1' class="type"><code id='Error.t-1'>type <a href='../../std/convert/trait.TryInto.html#associatedtype.Error' class="type">Error</a> = <U as <a class="trait" href="../../std/convert/trait.TryFrom.html" title="trait std::convert::TryFrom">TryFrom</a><T>>::<a class="type" href="../../std/convert/trait.TryFrom.html#associatedtype.Error" title="type std::convert::TryFrom::Error">Error</a></code></h4><div class='docblock'><p>The type returned in the event of a conversion error.</p>
</div><h4 id='method.try_into' class="method hidden"><code id='try_into.v'>fn <a href='../../std/convert/trait.TryInto.html#tymethod.try_into' class='fnname'>try_into</a>(self) -> <a class="enum" href="../../std/result/enum.Result.html" title="enum std::result::Result">Result</a><U, <U as <a class="trait" href="../../std/convert/trait.TryFrom.html" title="trait std::convert::TryFrom">TryFrom</a><T>>::<a class="type" href="../../std/convert/trait.TryFrom.html#associatedtype.Error" title="type std::convert::TryFrom::Error">Error</a>></code><a class='srclink' href='../../src/core/convert.rs.html#557-559' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Performs the conversion.</p>
</div></div><h3 id='impl-Into' class='impl'><code class='in-band'>impl<T, U> <a class="trait" href="../../std/convert/trait.Into.html" title="trait std::convert::Into">Into</a> for T <span class="where fmt-newline">where<br> U: <a class="trait" href="../../std/convert/trait.From.html" title="trait std::convert::From">From</a><T>, </span></code><a href='#impl-Into' class='anchor'></a><a class='srclink' href='../../src/core/convert.rs.html#537-542' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.into' class="method hidden"><code id='into.v'>fn <a href='../../std/convert/trait.Into.html#tymethod.into' class='fnname'>into</a>(self) -> U</code><a class='srclink' href='../../src/core/convert.rs.html#539-541' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Performs the conversion.</p>
</div></div><h3 id='impl-Borrow' class='impl'><code class='in-band'>impl<T> <a class="trait" href="../../std/borrow/trait.Borrow.html" title="trait std::borrow::Borrow">Borrow</a> for T <span class="where fmt-newline">where<br> T: ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></code><a href='#impl-Borrow' class='anchor'></a><a class='srclink' href='../../src/core/borrow.rs.html#213-215' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.borrow' class="method hidden"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F</h3><code class="content"><span class="where fmt-newline">impl<'_, F> <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F <span class="where fmt-newline">where<br> F: <a class="trait" href="../../std/marker/trait.Unpin.html" title="trait std::marker::Unpin">Unpin</a> + <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../std/future/trait.Future.html#associatedtype.Output' class="type">Output</a> = <F as <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a>>::<a class="type" href="../../std/future/trait.Future.html#associatedtype.Output" title="type std::future::Future::Output">Output</a>;</span><span class="where fmt-newline">impl<'_, I> <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>I <span class="where fmt-newline">where<br> I: <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../std/iter/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = <I as <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a>>::<a class="type" href="../../std/iter/trait.Iterator.html#associatedtype.Item" title="type std::iter::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl<R: <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, '_> <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>R</span><span class="where fmt-newline">impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, '_> <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>W</span></code></div></div><code id='borrow.v'>fn <a href='../../std/borrow/trait.Borrow.html#tymethod.borrow' class='fnname'>borrow</a>(&self) -> <a class="primitive" href="../primitive.reference.html">&</a>T</code><a class='srclink' href='../../src/core/borrow.rs.html#214' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Immutably borrows from an owned value. <a href="../../std/borrow/trait.Borrow.html#tymethod.borrow">Read more</a></p>
</div></div><h3 id='impl-BorrowMut' class='impl'><code class='in-band'>impl<T> <a class="trait" href="../../std/borrow/trait.BorrowMut.html" title="trait std::borrow::BorrowMut">BorrowMut</a> for T <span class="where fmt-newline">where<br> T: ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></code><a href='#impl-BorrowMut' class='anchor'></a><a class='srclink' href='../../src/core/borrow.rs.html#218-220' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.borrow_mut' class="method hidden"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F</h3><code class="content"><span class="where fmt-newline">impl<'_, F> <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>F <span class="where fmt-newline">where<br> F: <a class="trait" href="../../std/marker/trait.Unpin.html" title="trait std::marker::Unpin">Unpin</a> + <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../std/future/trait.Future.html#associatedtype.Output' class="type">Output</a> = <F as <a class="trait" href="../../std/future/trait.Future.html" title="trait std::future::Future">Future</a>>::<a class="type" href="../../std/future/trait.Future.html#associatedtype.Output" title="type std::future::Future::Output">Output</a>;</span><span class="where fmt-newline">impl<'_, I> <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>I <span class="where fmt-newline">where<br> I: <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../std/iter/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = <I as <a class="trait" href="../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a>>::<a class="type" href="../../std/iter/trait.Iterator.html#associatedtype.Item" title="type std::iter::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl<R: <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, '_> <a class="trait" href="../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>R</span><span class="where fmt-newline">impl<W: <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, '_> <a class="trait" href="../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="../primitive.reference.html">&'_ mut </a>W</span></code></div></div><code id='borrow_mut.v'>fn <a href='../../std/borrow/trait.BorrowMut.html#tymethod.borrow_mut' class='fnname'>borrow_mut</a>(&mut self) -> <a class="primitive" href="../primitive.reference.html">&mut </a>T</code><a class='srclink' href='../../src/core/borrow.rs.html#219' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Mutably borrows from an owned value. <a href="../../std/borrow/trait.BorrowMut.html#tymethod.borrow_mut">Read more</a></p>
</div></div><h3 id='impl-Any' class='impl'><code class='in-band'>impl<T> <a class="trait" href="../../std/any/trait.Any.html" title="trait std::any::Any">Any</a> for T <span class="where fmt-newline">where<br> T: 'static + ?<a class="trait" href="../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></code><a href='#impl-Any' class='anchor'></a><a class='srclink' href='../../src/core/any.rs.html#100-102' title='goto source code'>[src]</a></h3><div class='impl-items'><h4 id='method.type_id' class="method hidden"><code id='type_id.v'>fn <a href='../../std/any/trait.Any.html#tymethod.type_id' class='fnname'>type_id</a>(&self) -> <a class="struct" href="../../std/any/struct.TypeId.html" title="struct std::any::TypeId">TypeId</a></code><a class='srclink' href='../../src/core/any.rs.html#101' title='goto source code'>[src]</a></h4><div class='docblock hidden'><p>Gets the <code>TypeId</code> of <code>self</code>. <a href="../../std/any/trait.Any.html#tymethod.type_id">Read more</a></p>
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