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<p class='location'>Trait UpperExp</p><div class="block items"><ul><li><a href="#required-methods">Required Methods</a></li><li><a href="#implementors">Implementors</a></li></ul></div><p class='location'><a href='../index.html'>collections</a>::<wbr><a href='index.html'>fmt</a></p><script>window.sidebarCurrent = {name: 'UpperExp', ty: 'trait', relpath: ''};</script><script defer src="sidebar-items.js"></script>
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<h1 class='fqn'><span class='in-band'>Trait <a href='../index.html'>collections</a>::<wbr><a href='index.html'>fmt</a>::<wbr><a class="trait" href=''>UpperExp</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'>
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</span><a class='srclink' href='../../src/core/fmt/mod.rs.html#894-898' title='goto source code'>[src]</a></span></h1>
<pre class='rust trait'>pub trait UpperExp {
fn <a href='#tymethod.fmt' class='fnname'>fmt</a>(&self, f: &mut <a class="struct" href="../../collections/fmt/struct.Formatter.html" title="struct collections::fmt::Formatter">Formatter</a>) -> <a class="enum" href="../../core/result/enum.Result.html" title="enum core::result::Result">Result</a><(), <a class="struct" href="../../collections/fmt/struct.Error.html" title="struct collections::fmt::Error">Error</a>>;
}</pre><div class='docblock'><p>Format trait for the <code>E</code> character.</p>
<p>The <code>UpperExp</code> trait should format its output in scientific notation with an upper-case <code>E</code>.</p>
<p>For more information on formatters, see <a href="../../std/fmt/index.html">the module-level documentation</a>.</p>
<h1 id='examples' class='section-header'><a href='#examples'>Examples</a></h1>
<p>Basic usage with <code>f32</code>:</p>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="number">42.0</span>; <span class="comment">// 42.0 is '4.2E1' in scientific notation</span>
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="macro">format</span><span class="macro">!</span>(<span class="string">"{:E}"</span>, <span class="ident">x</span>), <span class="string">"4.2E1"</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=fn%20main()%20%7B%0Alet%20x%20%3D%2042.0%3B%20%2F%2F%2042.0%20is%20'4.2E1'%20in%20scientific%20notation%0A%0Aassert_eq!(format!(%22%7B%3AE%7D%22%2C%20x)%2C%20%224.2E1%22)%3B%0A%7D">Run</a></pre>
<p>Implementing <code>UpperExp</code> on a type:</p>
<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">Length</span>(<span class="ident">i32</span>);
<span class="kw">impl</span> <span class="ident">fmt</span>::<span class="ident">UpperExp</span> <span class="kw">for</span> <span class="ident">Length</span> {
<span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">f</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-></span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> {
<span class="kw">let</span> <span class="ident">val</span> <span class="op">=</span> <span class="self">self</span>.<span class="number">0</span>;
<span class="macro">write</span><span class="macro">!</span>(<span class="ident">f</span>, <span class="string">"{}E1"</span>, <span class="ident">val</span> <span class="op">/</span> <span class="number">10</span>)
}
}
<span class="kw">let</span> <span class="ident">l</span> <span class="op">=</span> <span class="ident">Length</span>(<span class="number">100</span>);
<span class="macro">println</span><span class="macro">!</span>(<span class="string">"l in scientific notation is: {:E}"</span>, <span class="ident">l</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=fn%20main()%20%7B%0Ause%20std%3A%3Afmt%3B%0A%0Astruct%20Length(i32)%3B%0A%0Aimpl%20fmt%3A%3AUpperExp%20for%20Length%20%7B%0A%20%20%20%20fn%20fmt(%26self%2C%20f%3A%20%26mut%20fmt%3A%3AFormatter)%20-%3E%20fmt%3A%3AResult%20%7B%0A%20%20%20%20%20%20%20%20let%20val%20%3D%20self.0%3B%0A%20%20%20%20%20%20%20%20write!(f%2C%20%22%7B%7DE1%22%2C%20val%20%2F%2010)%0A%20%20%20%20%7D%0A%7D%0A%0Alet%20l%20%3D%20Length(100)%3B%0A%0Aprintln!(%22l%20in%20scientific%20notation%20is%3A%20%7B%3AE%7D%22%2C%20l)%3B%0A%7D">Run</a></pre>
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<h2 id='required-methods'>Required Methods</h2>
<div class='methods'>
<h3 id='tymethod.fmt' class='method'><span id='fmt.v' class='invisible'><code>fn <a href='#tymethod.fmt' class='fnname'>fmt</a>(&self, f: &mut <a class="struct" href="../../collections/fmt/struct.Formatter.html" title="struct collections::fmt::Formatter">Formatter</a>) -> <a class="enum" href="../../core/result/enum.Result.html" title="enum core::result::Result">Result</a><(), <a class="struct" href="../../collections/fmt/struct.Error.html" title="struct collections::fmt::Error">Error</a>></code></span></h3><div class='docblock'><p>Formats the value using the given formatter.</p>
</div></div>
<h2 id='implementors'>Implementors</h2>
<ul class='item-list' id='implementors-list'>
<li><code>impl<'a, T> UpperExp for &'a T <span class="where fmt-newline">where<br> T: <a class="trait" href="../../collections/fmt/trait.UpperExp.html" title="trait collections::fmt::UpperExp">UpperExp</a> + ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></li>
<li><code>impl<'a, T> UpperExp for &'a mut T <span class="where fmt-newline">where<br> T: <a class="trait" href="../../collections/fmt/trait.UpperExp.html" title="trait collections::fmt::UpperExp">UpperExp</a> + ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></li>
<li><code>impl UpperExp for f64</code></li>
<li><code>impl UpperExp for f32</code></li>
</ul><script type="text/javascript" async
src="../../implementors/core/fmt/trait.UpperExp.js">
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