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        <p class='location'>Struct Formatter</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#methods">Methods</a><div class="sidebar-links"><a href="#method.pad_integral">pad_integral</a><a href="#method.pad">pad</a><a href="#method.write_str">write_str</a><a href="#method.write_fmt">write_fmt</a><a href="#method.flags">flags</a><a href="#method.fill">fill</a><a href="#method.align">align</a><a href="#method.width">width</a><a href="#method.precision">precision</a><a href="#method.sign_plus">sign_plus</a><a href="#method.sign_minus">sign_minus</a><a href="#method.alternate">alternate</a><a href="#method.sign_aware_zero_pad">sign_aware_zero_pad</a><a href="#method.debug_struct">debug_struct</a><a href="#method.debug_tuple">debug_tuple</a><a href="#method.debug_list">debug_list</a><a href="#method.debug_set">debug_set</a><a href="#method.debug_map">debug_map</a></div><a class="sidebar-title" href="#implementations">Trait Implementations</a><div class="sidebar-links"><a href="#impl-Write">Write</a></div></div><p class='location'><a href='../index.html'>alloc</a>::<wbr><a href='index.html'>fmt</a></p><script>window.sidebarCurrent = {name: 'Formatter', ty: 'struct', relpath: ''};</script><script defer src="sidebar-items.js"></script></div>
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<h1 class='fqn'><span class='in-band'>Struct <a href='../index.html'>alloc</a>::<wbr><a href='index.html'>fmt</a>::<wbr><a class="struct" href=''>Formatter</a></span><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'>&#x2212;</span>]
                   </a>
               </span><a class='srclink' href='../../src/core/fmt/mod.rs.html#250-260' title='goto source code'>[src]</a></span></h1>
<pre class='rust struct'>pub struct Formatter&lt;'a&gt; { /* fields omitted */ }</pre><div class='docblock'><p>A struct to represent both where to emit formatting strings to and how they
should be formatted. A mutable version of this is passed to all formatting
traits.</p>
</div>
                    <h2 id='methods' class='small-section-header'>
                      Methods<a href='#methods' class='anchor'></a>
                    </h2>
                <h3 id='impl' class='impl'><span class='in-band'><code>impl&lt;'a&gt; <a class="struct" href="../../alloc/fmt/struct.Formatter.html" title="struct alloc::fmt::Formatter">Formatter</a>&lt;'a&gt;</code><a href='#impl' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1044-1535' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.pad_integral' class="method"><span id='pad_integral.v' class='invisible'><code>pub fn <a href='#method.pad_integral' class='fnname'>pad_integral</a>(<br>&nbsp;&nbsp;&nbsp;&nbsp;&amp;mut self, <br>&nbsp;&nbsp;&nbsp;&nbsp;is_nonnegative: bool, <br>&nbsp;&nbsp;&nbsp;&nbsp;prefix: &amp;str, <br>&nbsp;&nbsp;&nbsp;&nbsp;buf: &amp;str<br>) -&gt; <a class="enum" href="../../core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;(), <a class="struct" href="../../alloc/fmt/struct.Error.html" title="struct alloc::fmt::Error">Error</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1117-1174' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Performs the correct padding for an integer which has already been
emitted into a str. The str should <em>not</em> contain the sign for the
integer, that will be added by this method.</p>
<h1 id="arguments" class="section-header"><a href="#arguments">Arguments</a></h1>
<ul>
<li>is_nonnegative - whether the original integer was either positive or zero.</li>
<li>prefix - if the '#' character (Alternate) is provided, this
is the prefix to put in front of the number.</li>
<li>buf - the byte array that the number has been formatted into</li>
</ul>
<p>This function will correctly account for the flags provided as well as
the minimum width. It will not take precision into account.</p>
</div><h4 id='method.pad' class="method"><span id='pad.v' class='invisible'><code>pub fn <a href='#method.pad' class='fnname'>pad</a>(&amp;mut self, s: &amp;str) -&gt; <a class="enum" href="../../core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;(), <a class="struct" href="../../alloc/fmt/struct.Error.html" title="struct alloc::fmt::Error">Error</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1188-1226' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>This function takes a string slice and emits it to the internal buffer
after applying the relevant formatting flags specified. The flags
recognized for generic strings are:</p>
<ul>
<li>width - the minimum width of what to emit</li>
<li>fill/align - what to emit and where to emit it if the string
provided needs to be padded</li>
<li>precision - the maximum length to emit, the string is truncated if it
is longer than this length</li>
</ul>
<p>Notably this function ignores the <code>flag</code> parameters.</p>
</div><h4 id='method.write_str' class="method"><span id='write_str.v' class='invisible'><code>pub fn <a href='#method.write_str' class='fnname'>write_str</a>(&amp;mut self, data: &amp;str) -&gt; <a class="enum" href="../../core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;(), <a class="struct" href="../../alloc/fmt/struct.Error.html" title="struct alloc::fmt::Error">Error</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1345-1347' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Writes some data to the underlying buffer contained within this
formatter.</p>
</div><h4 id='method.write_fmt' class="method"><span id='write_fmt.v' class='invisible'><code>pub fn <a href='#method.write_fmt' class='fnname'>write_fmt</a>(&amp;mut self, fmt: <a class="struct" href="../../alloc/fmt/struct.Arguments.html" title="struct alloc::fmt::Arguments">Arguments</a>) -&gt; <a class="enum" href="../../core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;(), <a class="struct" href="../../alloc/fmt/struct.Error.html" title="struct alloc::fmt::Error">Error</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1351-1353' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Writes some formatted information into this instance</p>
</div><h4 id='method.flags' class="method"><span id='flags.v' class='invisible'><code>pub fn <a href='#method.flags' class='fnname'>flags</a>(&amp;self) -&gt; u32</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1360' title='goto source code'>[src]</a></span></h4>
<div class='stability'><div class='stab deprecated'>Deprecated since 1.24.0<p>: use the <code>sign_plus</code>, <code>sign_minus</code>, <code>alternate</code>, or <code>sign_aware_zero_pad</code> methods instead</p>
</div></div><div class='docblock'><p>Flags for formatting</p>
</div><h4 id='method.fill' class="method"><span id='fill.v' class='invisible'><code>pub fn <a href='#method.fill' class='fnname'>fill</a>(&amp;self) -&gt; char</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.5.0'>1.5.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1364' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Character used as 'fill' whenever there is alignment</p>
</div><h4 id='method.align' class="method"><span id='align.v' class='invisible'><code>pub fn <a href='#method.align' class='fnname'>align</a>(&amp;self) -&gt; <a class="enum" href="../../core/fmt/enum.Alignment.html" title="enum core::fmt::Alignment">Alignment</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1369-1376' title='goto source code'>[src]</a></span></h4>
<div class='stability'><div class='stab unstable'><details><summary><span class=microscope>🔬</span> This is a nightly-only experimental API.  (<code>fmt_flags_align </code><a href="https://github.com/rust-lang/rust/issues/27726">#27726</a>)</summary><p>method was just created</p>
</details></div></div><div class='docblock'><p>Flag indicating what form of alignment was requested</p>
</div><h4 id='method.width' class="method"><span id='width.v' class='invisible'><code>pub fn <a href='#method.width' class='fnname'>width</a>(&amp;self) -&gt; <a class="enum" href="../../core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;usize&gt;</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.5.0'>1.5.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1380' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Optionally specified integer width that the output should be</p>
</div><h4 id='method.precision' class="method"><span id='precision.v' class='invisible'><code>pub fn <a href='#method.precision' class='fnname'>precision</a>(&amp;self) -&gt; <a class="enum" href="../../core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;usize&gt;</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.5.0'>1.5.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1384' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Optionally specified precision for numeric types</p>
</div><h4 id='method.sign_plus' class="method"><span id='sign_plus.v' class='invisible'><code>pub fn <a href='#method.sign_plus' class='fnname'>sign_plus</a>(&amp;self) -&gt; bool</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.5.0'>1.5.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1388' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Determines if the <code>+</code> flag was specified.</p>
</div><h4 id='method.sign_minus' class="method"><span id='sign_minus.v' class='invisible'><code>pub fn <a href='#method.sign_minus' class='fnname'>sign_minus</a>(&amp;self) -&gt; bool</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.5.0'>1.5.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1392' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Determines if the <code>-</code> flag was specified.</p>
</div><h4 id='method.alternate' class="method"><span id='alternate.v' class='invisible'><code>pub fn <a href='#method.alternate' class='fnname'>alternate</a>(&amp;self) -&gt; bool</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.5.0'>1.5.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1396' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Determines if the <code>#</code> flag was specified.</p>
</div><h4 id='method.sign_aware_zero_pad' class="method"><span id='sign_aware_zero_pad.v' class='invisible'><code>pub fn <a href='#method.sign_aware_zero_pad' class='fnname'>sign_aware_zero_pad</a>(&amp;self) -&gt; bool</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.5.0'>1.5.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1400-1402' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Determines if the <code>0</code> flag was specified.</p>
</div><h4 id='method.debug_struct' class="method"><span id='debug_struct.v' class='invisible'><code>pub fn <a href='#method.debug_struct' class='fnname'>debug_struct</a>(&amp;'b mut self, name: &amp;str) -&gt; <a class="struct" href="../../alloc/fmt/struct.DebugStruct.html" title="struct alloc::fmt::DebugStruct">DebugStruct</a>&lt;'b, 'a&gt;</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.2.0'>1.2.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1433-1435' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Creates a <a href="../../std/fmt/struct.DebugStruct.html"><code>DebugStruct</code></a> builder designed to assist with creation of
<a href="../../std/fmt/trait.Debug.html"><code>fmt::Debug</code></a> implementations for structs.</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">fmt</span>;

<span class="kw">struct</span> <span class="ident">Foo</span> {
    <span class="ident">bar</span>: <span class="ident">i32</span>,
    <span class="ident">baz</span>: <span class="ident">String</span>,
}

<span class="kw">impl</span> <span class="ident">fmt</span>::<span class="ident">Debug</span> <span class="kw">for</span> <span class="ident">Foo</span> {
    <span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">fmt</span>: <span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-&gt;</span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> {
        <span class="ident">fmt</span>.<span class="ident">debug_struct</span>(<span class="string">&quot;Foo&quot;</span>)
            .<span class="ident">field</span>(<span class="string">&quot;bar&quot;</span>, <span class="kw-2">&amp;</span><span class="self">self</span>.<span class="ident">bar</span>)
            .<span class="ident">field</span>(<span class="string">&quot;baz&quot;</span>, <span class="kw-2">&amp;</span><span class="self">self</span>.<span class="ident">baz</span>)
            .<span class="ident">finish</span>()
    }
}

<span class="comment">// prints &quot;Foo { bar: 10, baz: &quot;Hello World&quot; }&quot;</span>
<span class="macro">println</span><span class="macro">!</span>(<span class="string">&quot;{:?}&quot;</span>, <span class="ident">Foo</span> { <span class="ident">bar</span>: <span class="number">10</span>, <span class="ident">baz</span>: <span class="string">&quot;Hello World&quot;</span>.<span class="ident">to_string</span>() });</pre>
</div><h4 id='method.debug_tuple' class="method"><span id='debug_tuple.v' class='invisible'><code>pub fn <a href='#method.debug_tuple' class='fnname'>debug_tuple</a>(&amp;'b mut self, name: &amp;str) -&gt; <a class="struct" href="../../alloc/fmt/struct.DebugTuple.html" title="struct alloc::fmt::DebugTuple">DebugTuple</a>&lt;'b, 'a&gt;</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.2.0'>1.2.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1460-1462' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Creates a <code>DebugTuple</code> builder designed to assist with creation of
<code>fmt::Debug</code> implementations for tuple structs.</p>
<h1 id="examples-1" class="section-header"><a href="#examples-1">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">fmt</span>;

<span class="kw">struct</span> <span class="ident">Foo</span>(<span class="ident">i32</span>, <span class="ident">String</span>);

<span class="kw">impl</span> <span class="ident">fmt</span>::<span class="ident">Debug</span> <span class="kw">for</span> <span class="ident">Foo</span> {
    <span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">fmt</span>: <span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-&gt;</span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> {
        <span class="ident">fmt</span>.<span class="ident">debug_tuple</span>(<span class="string">&quot;Foo&quot;</span>)
            .<span class="ident">field</span>(<span class="kw-2">&amp;</span><span class="self">self</span>.<span class="number">0</span>)
            .<span class="ident">field</span>(<span class="kw-2">&amp;</span><span class="self">self</span>.<span class="number">1</span>)
            .<span class="ident">finish</span>()
    }
}

<span class="comment">// prints &quot;Foo(10, &quot;Hello World&quot;)&quot;</span>
<span class="macro">println</span><span class="macro">!</span>(<span class="string">&quot;{:?}&quot;</span>, <span class="ident">Foo</span>(<span class="number">10</span>, <span class="string">&quot;Hello World&quot;</span>.<span class="ident">to_string</span>()));</pre>
</div><h4 id='method.debug_list' class="method"><span id='debug_list.v' class='invisible'><code>pub fn <a href='#method.debug_list' class='fnname'>debug_list</a>(&amp;'b mut self) -&gt; <a class="struct" href="../../alloc/fmt/struct.DebugList.html" title="struct alloc::fmt::DebugList">DebugList</a>&lt;'b, 'a&gt;</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.2.0'>1.2.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1484-1486' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Creates a <code>DebugList</code> builder designed to assist with creation of
<code>fmt::Debug</code> implementations for list-like structures.</p>
<h1 id="examples-2" class="section-header"><a href="#examples-2">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">fmt</span>;

<span class="kw">struct</span> <span class="ident">Foo</span>(<span class="ident">Vec</span><span class="op">&lt;</span><span class="ident">i32</span><span class="op">&gt;</span>);

<span class="kw">impl</span> <span class="ident">fmt</span>::<span class="ident">Debug</span> <span class="kw">for</span> <span class="ident">Foo</span> {
    <span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">fmt</span>: <span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-&gt;</span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> {
        <span class="ident">fmt</span>.<span class="ident">debug_list</span>().<span class="ident">entries</span>(<span class="self">self</span>.<span class="number">0</span>.<span class="ident">iter</span>()).<span class="ident">finish</span>()
    }
}

<span class="comment">// prints &quot;[10, 11]&quot;</span>
<span class="macro">println</span><span class="macro">!</span>(<span class="string">&quot;{:?}&quot;</span>, <span class="ident">Foo</span>(<span class="macro">vec</span><span class="macro">!</span>[<span class="number">10</span>, <span class="number">11</span>]));</pre>
</div><h4 id='method.debug_set' class="method"><span id='debug_set.v' class='invisible'><code>pub fn <a href='#method.debug_set' class='fnname'>debug_set</a>(&amp;'b mut self) -&gt; <a class="struct" href="../../alloc/fmt/struct.DebugSet.html" title="struct alloc::fmt::DebugSet">DebugSet</a>&lt;'b, 'a&gt;</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.2.0'>1.2.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1508-1510' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Creates a <code>DebugSet</code> builder designed to assist with creation of
<code>fmt::Debug</code> implementations for set-like structures.</p>
<h1 id="examples-3" class="section-header"><a href="#examples-3">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">fmt</span>;

<span class="kw">struct</span> <span class="ident">Foo</span>(<span class="ident">Vec</span><span class="op">&lt;</span><span class="ident">i32</span><span class="op">&gt;</span>);

<span class="kw">impl</span> <span class="ident">fmt</span>::<span class="ident">Debug</span> <span class="kw">for</span> <span class="ident">Foo</span> {
    <span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">fmt</span>: <span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-&gt;</span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> {
        <span class="ident">fmt</span>.<span class="ident">debug_set</span>().<span class="ident">entries</span>(<span class="self">self</span>.<span class="number">0</span>.<span class="ident">iter</span>()).<span class="ident">finish</span>()
    }
}

<span class="comment">// prints &quot;{10, 11}&quot;</span>
<span class="macro">println</span><span class="macro">!</span>(<span class="string">&quot;{:?}&quot;</span>, <span class="ident">Foo</span>(<span class="macro">vec</span><span class="macro">!</span>[<span class="number">10</span>, <span class="number">11</span>]));</pre>
</div><h4 id='method.debug_map' class="method"><span id='debug_map.v' class='invisible'><code>pub fn <a href='#method.debug_map' class='fnname'>debug_map</a>(&amp;'b mut self) -&gt; <a class="struct" href="../../alloc/fmt/struct.DebugMap.html" title="struct alloc::fmt::DebugMap">DebugMap</a>&lt;'b, 'a&gt;</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.2.0'>1.2.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1532-1534' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Creates a <code>DebugMap</code> builder designed to assist with creation of
<code>fmt::Debug</code> implementations for map-like structures.</p>
<h1 id="examples-4" class="section-header"><a href="#examples-4">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">fmt</span>;

<span class="kw">struct</span> <span class="ident">Foo</span>(<span class="ident">Vec</span><span class="op">&lt;</span>(<span class="ident">String</span>, <span class="ident">i32</span>)<span class="op">&gt;</span>);

<span class="kw">impl</span> <span class="ident">fmt</span>::<span class="ident">Debug</span> <span class="kw">for</span> <span class="ident">Foo</span> {
    <span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">fmt</span>: <span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-&gt;</span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> {
        <span class="ident">fmt</span>.<span class="ident">debug_map</span>().<span class="ident">entries</span>(<span class="self">self</span>.<span class="number">0</span>.<span class="ident">iter</span>().<span class="ident">map</span>(<span class="op">|</span><span class="kw-2">&amp;</span>(<span class="kw-2">ref</span> <span class="ident">k</span>, <span class="kw-2">ref</span> <span class="ident">v</span>)<span class="op">|</span> (<span class="ident">k</span>, <span class="ident">v</span>))).<span class="ident">finish</span>()
    }
}

<span class="comment">// prints &quot;{&quot;A&quot;: 10, &quot;B&quot;: 11}&quot;</span>
<span class="macro">println</span><span class="macro">!</span>(<span class="string">&quot;{:?}&quot;</span>, <span class="ident">Foo</span>(<span class="macro">vec</span><span class="macro">!</span>[(<span class="string">&quot;A&quot;</span>.<span class="ident">to_string</span>(), <span class="number">10</span>), (<span class="string">&quot;B&quot;</span>.<span class="ident">to_string</span>(), <span class="number">11</span>)]));</pre>
</div></div>
            <h2 id='implementations' class='small-section-header'>
              Trait Implementations<a href='#implementations' class='anchor'></a>
            </h2>
        <h3 id='impl-Write' class='impl'><span class='in-band'><code>impl&lt;'a&gt; <a class="trait" href="../../alloc/fmt/trait.Write.html" title="trait alloc::fmt::Write">Write</a> for <a class="struct" href="../../alloc/fmt/struct.Formatter.html" title="struct alloc::fmt::Formatter">Formatter</a>&lt;'a&gt;</code><a href='#impl-Write' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.2.0'>1.2.0</div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1538-1550' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.write_str-1' class="method"><span id='write_str.v-1' class='invisible'><code>fn <a href='../../alloc/fmt/trait.Write.html#tymethod.write_str' class='fnname'>write_str</a>(&amp;mut self, s: &amp;str) -&gt; <a class="enum" href="../../core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;(), <a class="struct" href="../../alloc/fmt/struct.Error.html" title="struct alloc::fmt::Error">Error</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1539-1541' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Writes a slice of bytes into this writer, returning whether the write succeeded. <a href="../../alloc/fmt/trait.Write.html#tymethod.write_str">Read more</a></p>
</div><h4 id='method.write_char' class="method"><span id='write_char.v' class='invisible'><code>fn <a href='../../alloc/fmt/trait.Write.html#method.write_char' class='fnname'>write_char</a>(&amp;mut self, c: char) -&gt; <a class="enum" href="../../core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;(), <a class="struct" href="../../alloc/fmt/struct.Error.html" title="struct alloc::fmt::Error">Error</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1543-1545' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Writes a [<code>char</code>] into this writer, returning whether the write succeeded. <a href="../../alloc/fmt/trait.Write.html#method.write_char">Read more</a></p>
</div><h4 id='method.write_fmt-1' class="method"><span id='write_fmt.v-1' class='invisible'><code>fn <a href='../../alloc/fmt/trait.Write.html#method.write_fmt' class='fnname'>write_fmt</a>(&amp;mut self, args: <a class="struct" href="../../alloc/fmt/struct.Arguments.html" title="struct alloc::fmt::Arguments">Arguments</a>) -&gt; <a class="enum" href="../../core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;(), <a class="struct" href="../../alloc/fmt/struct.Error.html" title="struct alloc::fmt::Error">Error</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#1547-1549' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Glue for usage of the [<code>write!</code>] macro with implementors of this trait. <a href="../../alloc/fmt/trait.Write.html#method.write_fmt">Read more</a></p>
</div></div></section>
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