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<p class='location'>Struct FromUtf8Error</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#methods">Methods</a><div class="sidebar-links"><a href="#method.as_bytes">as_bytes</a><a href="#method.into_bytes">into_bytes</a><a href="#method.utf8_error">utf8_error</a></div><a class="sidebar-title" href="#implementations">Trait Implementations</a><div class="sidebar-links"><a href="#impl-Debug">Debug</a><a href="#impl-Display">Display</a></div></div><p class='location'><a href='../index.html'>alloc</a>::<wbr><a href='index.html'>string</a></p><script>window.sidebarCurrent = {name: 'FromUtf8Error', 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'>string</a>::<wbr><a class="struct" href=''>FromUtf8Error</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'>−</span>]
</a>
</span><a class='srclink' href='../../src/alloc/string.rs.html#335-338' title='goto source code'>[src]</a></span></h1>
<pre class='rust struct'>pub struct FromUtf8Error { /* fields omitted */ }</pre><div class='docblock'><p>A possible error value when converting a <code>String</code> from a UTF-8 byte vector.</p>
<p>This type is the error type for the <a href="struct.String.html#method.from_utf8"><code>from_utf8</code></a> method on <a href="struct.String.html"><code>String</code></a>. It
is designed in such a way to carefully avoid reallocations: the
<a href="struct.FromUtf8Error.html#method.into_bytes"><code>into_bytes</code></a> method will give back the byte vector that was used in the
conversion attempt.</p>
<p>The <a href="../../std/str/struct.Utf8Error.html"><code>Utf8Error</code></a> type provided by <a href="../../std/str/index.html"><code>std::str</code></a> represents an error that may
occur when converting a slice of <a href="../../std/primitive.u8.html"><code>u8</code></a>s to a <a href="../../std/primitive.str.html"><code>&str</code></a>. In this sense, it's
an analogue to <code>FromUtf8Error</code>, and you can get one from a <code>FromUtf8Error</code>
through the <a href="#method.utf8_error"><code>utf8_error</code></a> method.</p>
<h1 id="examples" class="section-header"><a href="#examples">Examples</a></h1>
<p>Basic usage:</p>
<pre class="rust rust-example-rendered">
<span class="comment">// some invalid bytes, in a vector</span>
<span class="kw">let</span> <span class="ident">bytes</span> <span class="op">=</span> <span class="macro">vec</span><span class="macro">!</span>[<span class="number">0</span>, <span class="number">159</span>];
<span class="kw">let</span> <span class="ident">value</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from_utf8</span>(<span class="ident">bytes</span>);
<span class="macro">assert</span><span class="macro">!</span>(<span class="ident">value</span>.<span class="ident">is_err</span>());
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="macro">vec</span><span class="macro">!</span>[<span class="number">0</span>, <span class="number">159</span>], <span class="ident">value</span>.<span class="ident">unwrap_err</span>().<span class="ident">into_bytes</span>());</pre>
</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 <a class="struct" href="../../alloc/string/struct.FromUtf8Error.html" title="struct alloc::string::FromUtf8Error">FromUtf8Error</a></code><a href='#impl' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/alloc/string.rs.html#1497-1570' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.as_bytes' class="method"><span id='as_bytes.v' class='invisible'><code>pub fn <a href='#method.as_bytes' class='fnname'>as_bytes</a>(&self) -> &[u8]</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/alloc/string.rs.html#1514-1516' 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>from_utf8_error_as_bytes </code><a href="https://github.com/rust-lang/rust/issues/40895">#40895</a>)</summary><p>recently added</p>
</details></div></div><div class='docblock'><p>Returns a slice of [<code>u8</code>]s bytes that were attempted to convert to a <code>String</code>.</p>
<h1 id="examples-1" class="section-header"><a href="#examples-1">Examples</a></h1>
<p>Basic usage:</p>
<pre class="rust rust-example-rendered">
<span class="attribute">#![<span class="ident">feature</span>(<span class="ident">from_utf8_error_as_bytes</span>)]</span>
<span class="comment">// some invalid bytes, in a vector</span>
<span class="kw">let</span> <span class="ident">bytes</span> <span class="op">=</span> <span class="macro">vec</span><span class="macro">!</span>[<span class="number">0</span>, <span class="number">159</span>];
<span class="kw">let</span> <span class="ident">value</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from_utf8</span>(<span class="ident">bytes</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="kw-2">&</span>[<span class="number">0</span>, <span class="number">159</span>], <span class="ident">value</span>.<span class="ident">unwrap_err</span>().<span class="ident">as_bytes</span>());</pre>
</div><h4 id='method.into_bytes' class="method"><span id='into_bytes.v' class='invisible'><code>pub fn <a href='#method.into_bytes' class='fnname'>into_bytes</a>(self) -> <a class="struct" href="../../alloc/vec/struct.Vec.html" title="struct alloc::vec::Vec">Vec</a><u8></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/alloc/string.rs.html#1537-1539' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Returns the bytes that were attempted to convert to a <code>String</code>.</p>
<p>This method is carefully constructed to avoid allocation. It will
consume the error, moving out the bytes, so that a copy of the bytes
does not need to be made.</p>
<h1 id="examples-2" class="section-header"><a href="#examples-2">Examples</a></h1>
<p>Basic usage:</p>
<pre class="rust rust-example-rendered">
<span class="comment">// some invalid bytes, in a vector</span>
<span class="kw">let</span> <span class="ident">bytes</span> <span class="op">=</span> <span class="macro">vec</span><span class="macro">!</span>[<span class="number">0</span>, <span class="number">159</span>];
<span class="kw">let</span> <span class="ident">value</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from_utf8</span>(<span class="ident">bytes</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="macro">vec</span><span class="macro">!</span>[<span class="number">0</span>, <span class="number">159</span>], <span class="ident">value</span>.<span class="ident">unwrap_err</span>().<span class="ident">into_bytes</span>());</pre>
</div><h4 id='method.utf8_error' class="method"><span id='utf8_error.v' class='invisible'><code>pub fn <a href='#method.utf8_error' class='fnname'>utf8_error</a>(&self) -> <a class="struct" href="../../alloc/str/struct.Utf8Error.html" title="struct alloc::str::Utf8Error">Utf8Error</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/alloc/string.rs.html#1567-1569' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Fetch a <code>Utf8Error</code> to get more details about the conversion failure.</p>
<p>The <a href="../../std/str/struct.Utf8Error.html"><code>Utf8Error</code></a> type provided by <a href="../../std/str/index.html"><code>std::str</code></a> represents an error that may
occur when converting a slice of <a href="../../std/primitive.u8.html"><code>u8</code></a>s to a <a href="../../std/primitive.str.html"><code>&str</code></a>. In this sense, it's
an analogue to <code>FromUtf8Error</code>. See its documentation for more details
on using it.</p>
<h1 id="examples-3" class="section-header"><a href="#examples-3">Examples</a></h1>
<p>Basic usage:</p>
<pre class="rust rust-example-rendered">
<span class="comment">// some invalid bytes, in a vector</span>
<span class="kw">let</span> <span class="ident">bytes</span> <span class="op">=</span> <span class="macro">vec</span><span class="macro">!</span>[<span class="number">0</span>, <span class="number">159</span>];
<span class="kw">let</span> <span class="ident">error</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from_utf8</span>(<span class="ident">bytes</span>).<span class="ident">unwrap_err</span>().<span class="ident">utf8_error</span>();
<span class="comment">// the first byte is invalid here</span>
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="number">1</span>, <span class="ident">error</span>.<span class="ident">valid_up_to</span>());</pre>
</div></div>
<h2 id='implementations' class='small-section-header'>
Trait Implementations<a href='#implementations' class='anchor'></a>
</h2>
<h3 id='impl-Debug' class='impl'><span class='in-band'><code>impl <a class="trait" href="../../alloc/fmt/trait.Debug.html" title="trait alloc::fmt::Debug">Debug</a> for <a class="struct" href="../../alloc/string/struct.FromUtf8Error.html" title="struct alloc::string::FromUtf8Error">FromUtf8Error</a></code><a href='#impl-Debug' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/alloc/string.rs.html#334' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.fmt' class="method"><span id='fmt.v' class='invisible'><code>fn <a href='../../alloc/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&self, __arg_0: &mut <a class="struct" href="../../alloc/fmt/struct.Formatter.html" title="struct alloc::fmt::Formatter">Formatter</a>) -> <a class="type" href="../../alloc/fmt/type.Result.html" title="type alloc::fmt::Result">Result</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/alloc/string.rs.html#334' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Formats the value using the given formatter. <a href="../../alloc/fmt/trait.Debug.html#tymethod.fmt">Read more</a></p>
</div></div><h3 id='impl-Display' class='impl'><span class='in-band'><code>impl <a class="trait" href="../../alloc/fmt/trait.Display.html" title="trait alloc::fmt::Display">Display</a> for <a class="struct" href="../../alloc/string/struct.FromUtf8Error.html" title="struct alloc::string::FromUtf8Error">FromUtf8Error</a></code><a href='#impl-Display' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/alloc/string.rs.html#1573-1577' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.fmt-1' class="method"><span id='fmt.v-1' class='invisible'><code>fn <a href='../../alloc/fmt/trait.Display.html#tymethod.fmt' class='fnname'>fmt</a>(&self, f: &mut <a class="struct" href="../../alloc/fmt/struct.Formatter.html" title="struct alloc::fmt::Formatter">Formatter</a>) -> <a class="type" href="../../alloc/fmt/type.Result.html" title="type alloc::fmt::Result">Result</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/alloc/string.rs.html#1574-1576' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Formats the value using the given formatter. <a href="../../alloc/fmt/trait.Display.html#tymethod.fmt">Read more</a></p>
</div></div></section>
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