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<!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="The `Error` type, a wrapper around a dynamic error type."><title>Error in anyhow - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-46f98efaafac5295.ttf.woff2,FiraSans-Regular-018c141bf0843ffd.woff2,FiraSans-Medium-8f9a781e4970d388.woff2,SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2,SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2" crossorigin href="../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../static.files/rustdoc-dd39b87e5fcfba68.css"><meta name="rustdoc-vars" data-root-path="../" data-static-root-path="../static.files/" data-current-crate="anyhow" data-themes="" data-resource-suffix="" data-rustdoc-version="1.80.0 (051478957 2024-07-21)" data-channel="1.80.0" data-search-js="search-d52510db62a78183.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../static.files/storage-118b08c4c78b968e.js"></script><script defer src="sidebar-items.js"></script><script defer src="../static.files/main-20a3ad099b048cf2.js"></script><noscript><link rel="stylesheet" href="../static.files/noscript-df360f571f6edeae.css"></noscript><link rel="alternate icon" type="image/png" href="../static.files/favicon-32x32-422f7d1d52889060.png"><link rel="icon" type="image/svg+xml" href="../static.files/favicon-2c020d218678b618.svg"></head><body class="rustdoc struct"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="mobile-topbar"><button class="sidebar-menu-toggle" title="show sidebar"></button></nav><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../anyhow/index.html">anyhow</a><span class="version">1.0.86</span></h2></div><h2 class="location"><a href="#">Error</a></h2><div class="sidebar-elems"><section><h3><a href="#implementations">Methods</a></h3><ul class="block method"><li><a href="#method.backtrace">backtrace</a></li><li><a href="#method.chain">chain</a></li><li><a href="#method.context">context</a></li><li><a href="#method.downcast">downcast</a></li><li><a href="#method.downcast_mut">downcast_mut</a></li><li><a href="#method.downcast_ref">downcast_ref</a></li><li><a href="#method.is">is</a></li><li><a href="#method.msg">msg</a></li><li><a href="#method.new">new</a></li><li><a href="#method.root_cause">root_cause</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block trait-implementation"><li><a href="#impl-AsRef%3Cdyn+Error+%2B+Send+%2B+Sync%3E-for-Error">AsRef&lt;dyn Error + Sync + Send&gt;</a></li><li><a href="#impl-AsRef%3Cdyn+Error%3E-for-Error">AsRef&lt;dyn Error&gt;</a></li><li><a href="#impl-Debug-for-Error">Debug</a></li><li><a href="#impl-Deref-for-Error">Deref</a></li><li><a href="#impl-DerefMut-for-Error">DerefMut</a></li><li><a href="#impl-Display-for-Error">Display</a></li><li><a href="#impl-Drop-for-Error">Drop</a></li><li><a href="#impl-From%3CE%3E-for-Error">From&lt;E&gt;</a></li><li><a href="#impl-From%3CError%3E-for-Box%3Cdyn+Error%3E">From&lt;Error&gt;</a></li><li><a href="#impl-From%3CError%3E-for-Box%3Cdyn+Error+%2B+Send%3E">From&lt;Error&gt;</a></li><li><a href="#impl-From%3CError%3E-for-Box%3Cdyn+Error+%2B+Send+%2B+Sync%3E">From&lt;Error&gt;</a></li></ul><h3><a href="#synthetic-implementations">Auto Trait Implementations</a></h3><ul class="block synthetic-implementation"><li><a href="#impl-Freeze-for-Error">Freeze</a></li><li><a href="#impl-RefUnwindSafe-for-Error">RefUnwindSafe</a></li><li><a href="#impl-Send-for-Error">Send</a></li><li><a href="#impl-Sync-for-Error">Sync</a></li><li><a href="#impl-Unpin-for-Error">Unpin</a></li><li><a href="#impl-UnwindSafe-for-Error">UnwindSafe</a></li></ul><h3><a href="#blanket-implementations">Blanket Implementations</a></h3><ul class="block blanket-implementation"><li><a href="#impl-Any-for-T">Any</a></li><li><a href="#impl-Borrow%3CT%3E-for-T">Borrow&lt;T&gt;</a></li><li><a href="#impl-BorrowMut%3CT%3E-for-T">BorrowMut&lt;T&gt;</a></li><li><a href="#impl-From%3C!%3E-for-T">From&lt;!&gt;</a></li><li><a href="#impl-From%3CT%3E-for-T">From&lt;T&gt;</a></li><li><a href="#impl-Into%3CU%3E-for-T">Into&lt;U&gt;</a></li><li><a href="#impl-ToString-for-T">ToString</a></li><li><a href="#impl-TryFrom%3CU%3E-for-T">TryFrom&lt;U&gt;</a></li><li><a href="#impl-TryInto%3CU%3E-for-T">TryInto&lt;U&gt;</a></li></ul></section><h2><a href="index.html">In crate anyhow</a></h2></div></nav><div class="sidebar-resizer"></div><main><div class="width-limiter"><rustdoc-search></rustdoc-search><section id="main-content" class="content"><div class="main-heading"><h1>Struct <a href="index.html">anyhow</a>::<wbr><a class="struct" href="#">Error</a><button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><span class="out-of-band"><a class="src" href="../src/anyhow/lib.rs.html#387-389">source</a> · <button id="toggle-all-docs" title="collapse all docs">[<span>&#x2212;</span>]</button></span></div><pre class="rust item-decl"><code>pub struct Error { <span class="comment">/* private fields */</span> }</code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>The <code>Error</code> type, a wrapper around a dynamic error type.</p>
<p><code>Error</code> works a lot like <code>Box&lt;dyn std::error::Error&gt;</code>, but with these
differences:</p>
<ul>
<li><code>Error</code> requires that the error is <code>Send</code>, <code>Sync</code>, and <code>'static</code>.</li>
<li><code>Error</code> guarantees that a backtrace is available, even if the underlying
error type does not provide one.</li>
<li><code>Error</code> is represented as a narrow pointer — exactly one word in
size instead of two.</li>
</ul>
<br>
<h2 id="display-representations"><a class="doc-anchor" href="#display-representations">§</a>Display representations</h2>
<p>When you print an error object using “{}” or to_string(), only the outermost
underlying error or context is printed, not any of the lower level causes.
This is exactly as if you had called the Display impl of the error from
which you constructed your anyhow::Error.</p>
<div class="example-wrap"><pre class="language-console"><code>Failed to read instrs from ./path/to/instrs.json
</code></pre></div>
<p>To print causes as well using anyhow’s default formatting of causes, use the
alternate selector “{:#}”.</p>
<div class="example-wrap"><pre class="language-console"><code>Failed to read instrs from ./path/to/instrs.json: No such file or directory (os error 2)
</code></pre></div>
<p>The Debug format “{:?}” includes your backtrace if one was captured. Note
that this is the representation you get by default if you return an error
from <code>fn main</code> instead of printing it explicitly yourself.</p>
<div class="example-wrap"><pre class="language-console"><code>Error: Failed to read instrs from ./path/to/instrs.json
Caused by:
No such file or directory (os error 2)
</code></pre></div>
<p>and if there is a backtrace available:</p>
<div class="example-wrap"><pre class="language-console"><code>Error: Failed to read instrs from ./path/to/instrs.json
Caused by:
No such file or directory (os error 2)
Stack backtrace:
0: &lt;E as anyhow::context::ext::StdError&gt;::ext_context
at /git/anyhow/src/backtrace.rs:26
1: core::result::Result&lt;T,E&gt;::map_err
at /git/rustc/src/libcore/result.rs:596
2: anyhow::context::&lt;impl anyhow::Context&lt;T,E&gt; for core::result::Result&lt;T,E&gt;&gt;::with_context
at /git/anyhow/src/context.rs:58
3: testing::main
at src/main.rs:5
4: std::rt::lang_start
at /git/rustc/src/libstd/rt.rs:61
5: main
6: __libc_start_main
7: _start
</code></pre></div>
<p>To see a conventional struct-style Debug representation, use “{:#?}”.</p>
<div class="example-wrap"><pre class="language-console"><code>Error {
context: &quot;Failed to read instrs from ./path/to/instrs.json&quot;,
source: Os {
code: 2,
kind: NotFound,
message: &quot;No such file or directory&quot;,
},
}
</code></pre></div>
<p>If none of the built-in representations are appropriate and you would prefer
to render the error and its cause chain yourself, it can be done something
like this:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>anyhow::{Context, <span class="prelude-ty">Result</span>};
<span class="kw">fn </span>main() {
<span class="kw">if let </span><span class="prelude-val">Err</span>(err) = try_main() {
<span class="macro">eprintln!</span>(<span class="string">"ERROR: {}"</span>, err);
err.chain().skip(<span class="number">1</span>).for_each(|cause| <span class="macro">eprintln!</span>(<span class="string">"because: {}"</span>, cause));
std::process::exit(<span class="number">1</span>);
}
}
<span class="kw">fn </span>try_main() -&gt; <span class="prelude-ty">Result</span>&lt;()&gt; {
...
}</code></pre></div>
</div></details><h2 id="implementations" class="section-header">Implementations<a href="#implementations" class="anchor">§</a></h2><div id="implementations-list"><details class="toggle implementors-toggle" open><summary><section id="impl-Error" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#20-555">source</a><a href="#impl-Error" class="anchor">§</a><h3 class="code-header">impl <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.new" class="method"><a class="src rightside" href="../src/anyhow/error.rs.html#32-38">source</a><h4 class="code-header">pub fn <a href="#method.new" class="fn">new</a>&lt;E&gt;(error: E) -&gt; Self<div class="where">where
E: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">StdError</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + 'static,</div></h4></section></summary><div class="docblock"><p>Create a new error object from any error type.</p>
<p>The error type must be threadsafe and <code>'static</code>, so that the <code>Error</code>
will be as well.</p>
<p>If the error type does not provide a backtrace, a backtrace will be
created here to ensure that a backtrace exists.</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.msg" class="method"><a class="src rightside" href="../src/anyhow/error.rs.html#79-84">source</a><h4 class="code-header">pub fn <a href="#method.msg" class="fn">msg</a>&lt;M&gt;(message: M) -&gt; Self<div class="where">where
M: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html" title="trait core::fmt::Display">Display</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + 'static,</div></h4></section></summary><div class="docblock"><p>Create a new error object from a printable error message.</p>
<p>If the argument implements std::error::Error, prefer <code>Error::new</code>
instead which preserves the underlying error’s cause chain and
backtrace. If the argument may or may not implement std::error::Error
now or in the future, use <code>anyhow!(err)</code> which handles either way
correctly.</p>
<p><code>Error::msg(&quot;...&quot;)</code> is equivalent to <code>anyhow!(&quot;...&quot;)</code> but occasionally
convenient in places where a function is preferable over a macro, such
as iterator or stream combinators:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>anyhow::{Error, <span class="prelude-ty">Result</span>};
<span class="kw">use </span>futures::stream::{Stream, StreamExt, TryStreamExt};
<span class="kw">async fn </span>demo&lt;S&gt;(stream: S) -&gt; <span class="prelude-ty">Result</span>&lt;Vec&lt;Output&gt;&gt;
<span class="kw">where
</span>S: Stream&lt;Item = Input&gt;,
{
stream
.then(ffi::do_some_work) <span class="comment">// returns Result&lt;Output, &amp;str&gt;
</span>.map_err(Error::msg)
.try_collect()
.<span class="kw">await
</span>}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.context" class="method"><a class="src rightside" href="../src/anyhow/error.rs.html#316-347">source</a><h4 class="code-header">pub fn <a href="#method.context" class="fn">context</a>&lt;C&gt;(self, context: C) -&gt; Self<div class="where">where
C: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html" title="trait core::fmt::Display">Display</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + 'static,</div></h4></section></summary><div class="docblock"><p>Wrap the error value with additional context.</p>
<p>For attaching context to a <code>Result</code> as it is propagated, the
<a href="trait.Context.html" title="trait anyhow::Context"><code>Context</code></a> extension trait may be more convenient than
this function.</p>
<p>The primary reason to use <code>error.context(...)</code> instead of
<code>result.context(...)</code> via the <code>Context</code> trait would be if the context
needs to depend on some data held by the underlying error:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>anyhow::Result;
<span class="kw">use </span>std::fs::File;
<span class="kw">use </span>std::path::Path;
<span class="kw">struct </span>ParseError {
line: usize,
column: usize,
}
<span class="kw">fn </span>parse_impl(file: File) -&gt; <span class="prelude-ty">Result</span>&lt;T, ParseError&gt; {
...
}
<span class="kw">pub fn </span>parse(path: <span class="kw">impl </span>AsRef&lt;Path&gt;) -&gt; <span class="prelude-ty">Result</span>&lt;T&gt; {
<span class="kw">let </span>file = File::open(<span class="kw-2">&amp;</span>path)<span class="question-mark">?</span>;
parse_impl(file).map_err(|error| {
<span class="kw">let </span>context = <span class="macro">format!</span>(
<span class="string">"only the first {} lines of {} are valid"</span>,
error.line, path.as_ref().display(),
);
anyhow::Error::new(error).context(context)
})
}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.backtrace" class="method"><a class="src rightside" href="../src/anyhow/error.rs.html#377-379">source</a><h4 class="code-header">pub fn <a href="#method.backtrace" class="fn">backtrace</a>(&amp;self) -&gt; &amp;<a class="struct" href="https://doc.rust-lang.org/1.80.0/std/backtrace/struct.Backtrace.html" title="struct std::backtrace::Backtrace">Backtrace</a></h4></section></summary><div class="docblock"><p>Get the backtrace for this Error.</p>
<p>In order for the backtrace to be meaningful, one of the two environment
variables <code>RUST_LIB_BACKTRACE=1</code> or <code>RUST_BACKTRACE=1</code> must be defined
and <code>RUST_LIB_BACKTRACE</code> must not be <code>0</code>. Backtraces are somewhat
expensive to capture in Rust, so we don’t necessarily want to be
capturing them all over the place all the time.</p>
<ul>
<li>If you want panics and errors to both have backtraces, set
<code>RUST_BACKTRACE=1</code>;</li>
<li>If you want only errors to have backtraces, set
<code>RUST_LIB_BACKTRACE=1</code>;</li>
<li>If you want only panics to have backtraces, set <code>RUST_BACKTRACE=1</code> and
<code>RUST_LIB_BACKTRACE=0</code>.</li>
</ul>
<h5 id="stability"><a class="doc-anchor" href="#stability">§</a>Stability</h5>
<p>Standard library backtraces are only available when using Rust ≥
1.65. On older compilers, this function is only available if the crate’s
“backtrace” feature is enabled, and will use the <code>backtrace</code> crate as
the underlying backtrace implementation. The return type of this
function on old compilers is <code>&amp;(impl Debug + Display)</code>.</p>
<div class="example-wrap"><pre class="language-toml"><code>[dependencies]
anyhow = { version = &quot;1.0&quot;, features = [&quot;backtrace&quot;] }
</code></pre></div></div></details><details class="toggle method-toggle" open><summary><section id="method.chain" class="method"><a class="src rightside" href="../src/anyhow/error.rs.html#405-407">source</a><h4 class="code-header">pub fn <a href="#method.chain" class="fn">chain</a>(&amp;self) -&gt; <a class="struct" href="struct.Chain.html" title="struct anyhow::Chain">Chain</a>&lt;'_&gt; <a href="#" class="tooltip" data-notable-ty="Chain&lt;&#39;_&gt;">ⓘ</a></h4></section></summary><div class="docblock"><p>An iterator of the chain of source errors contained by this Error.</p>
<p>This iterator will visit every error in the cause chain of this error
object, beginning with the error that this error object was created
from.</p>
<h5 id="example"><a class="doc-anchor" href="#example">§</a>Example</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>anyhow::Error;
<span class="kw">use </span>std::io;
<span class="kw">pub fn </span>underlying_io_error_kind(error: <span class="kw-2">&amp;</span>Error) -&gt; <span class="prelude-ty">Option</span>&lt;io::ErrorKind&gt; {
<span class="kw">for </span>cause <span class="kw">in </span>error.chain() {
<span class="kw">if let </span><span class="prelude-val">Some</span>(io_error) = cause.downcast_ref::&lt;io::Error&gt;() {
<span class="kw">return </span><span class="prelude-val">Some</span>(io_error.kind());
}
}
<span class="prelude-val">None
</span>}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.root_cause" class="method"><a class="src rightside" href="../src/anyhow/error.rs.html#416-418">source</a><h4 class="code-header">pub fn <a href="#method.root_cause" class="fn">root_cause</a>(&amp;self) -&gt; &amp;(dyn <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">StdError</a> + 'static)</h4></section></summary><div class="docblock"><p>The lowest level cause of this error — this error’s cause’s
cause’s cause etc.</p>
<p>The root cause is the last error in the iterator produced by
<a href="struct.Error.html#method.chain" title="method anyhow::Error::chain"><code>chain()</code></a>.</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.is" class="method"><a class="src rightside" href="../src/anyhow/error.rs.html#428-433">source</a><h4 class="code-header">pub fn <a href="#method.is" class="fn">is</a>&lt;E&gt;(&amp;self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/std/primitive.bool.html">bool</a><div class="where">where
E: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html" title="trait core::fmt::Display">Display</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + 'static,</div></h4></section></summary><div class="docblock"><p>Returns true if <code>E</code> is the type held by this error object.</p>
<p>For errors with context, this method returns true if <code>E</code> matches the
type of the context <code>C</code> <strong>or</strong> the type of the error on which the
context has been attached. For details about the interaction between
context and downcasting, <a href="trait.Context.html#effect-on-downcasting">see here</a>.</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.downcast" class="method"><a class="src rightside" href="../src/anyhow/error.rs.html#436-468">source</a><h4 class="code-header">pub fn <a href="#method.downcast" class="fn">downcast</a>&lt;E&gt;(self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.80.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;E, Self&gt;<div class="where">where
E: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html" title="trait core::fmt::Display">Display</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + 'static,</div></h4></section></summary><div class="docblock"><p>Attempt to downcast the error object to a concrete type.</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.downcast_ref" class="method"><a class="src rightside" href="../src/anyhow/error.rs.html#506-517">source</a><h4 class="code-header">pub fn <a href="#method.downcast_ref" class="fn">downcast_ref</a>&lt;E&gt;(&amp;self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.80.0/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/1.80.0/std/primitive.reference.html">&amp;E</a>&gt;<div class="where">where
E: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html" title="trait core::fmt::Display">Display</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + 'static,</div></h4></section></summary><div class="docblock"><p>Downcast this error object by reference.</p>
<h5 id="example-1"><a class="doc-anchor" href="#example-1">§</a>Example</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="comment">// If the error was caused by redaction, then return a tombstone instead
// of the content.
</span><span class="kw">match </span>root_cause.downcast_ref::&lt;DataStoreError&gt;() {
<span class="prelude-val">Some</span>(DataStoreError::Censored(<span class="kw">_</span>)) =&gt; <span class="prelude-val">Ok</span>(Poll::Ready(REDACTED_CONTENT)),
<span class="prelude-val">None </span>=&gt; <span class="prelude-val">Err</span>(error),
}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.downcast_mut" class="method"><a class="src rightside" href="../src/anyhow/error.rs.html#520-538">source</a><h4 class="code-header">pub fn <a href="#method.downcast_mut" class="fn">downcast_mut</a>&lt;E&gt;(&amp;mut self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.80.0/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/1.80.0/std/primitive.reference.html">&amp;mut E</a>&gt;<div class="where">where
E: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html" title="trait core::fmt::Display">Display</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + 'static,</div></h4></section></summary><div class="docblock"><p>Downcast this error object by mutable reference.</p>
</div></details></div></details></div><h2 id="trait-implementations" class="section-header">Trait Implementations<a href="#trait-implementations" class="anchor">§</a></h2><div id="trait-implementations-list"><details class="toggle implementors-toggle" open><summary><section id="impl-AsRef%3Cdyn+Error%3E-for-Error" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#1020-1024">source</a><a href="#impl-AsRef%3Cdyn+Error%3E-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.AsRef.html" title="trait core::convert::AsRef">AsRef</a>&lt;dyn <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">Error</a>&gt; for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.as_ref" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#1021-1023">source</a><a href="#method.as_ref" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.AsRef.html#tymethod.as_ref" class="fn">as_ref</a>(&amp;self) -&gt; &amp;(dyn <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">StdError</a> + 'static)</h4></section></summary><div class='docblock'>Converts this type into a shared reference of the (usually inferred) input type.</div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-AsRef%3Cdyn+Error+%2B+Send+%2B+Sync%3E-for-Error" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#1013-1017">source</a><a href="#impl-AsRef%3Cdyn+Error+%2B+Send+%2B+Sync%3E-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.AsRef.html" title="trait core::convert::AsRef">AsRef</a>&lt;dyn <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">Error</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a>&gt; for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.as_ref-1" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#1014-1016">source</a><a href="#method.as_ref-1" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.AsRef.html#tymethod.as_ref" class="fn">as_ref</a>(&amp;self) -&gt; &amp;(dyn <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">StdError</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + 'static)</h4></section></summary><div class='docblock'>Converts this type into a shared reference of the (usually inferred) input type.</div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-Debug-for-Error" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#594-598">source</a><a href="#impl-Debug-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.fmt" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#595-597">source</a><a href="#method.fmt" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html#tymethod.fmt" class="fn">fmt</a>(&amp;self, formatter: &amp;mut <a class="struct" href="https://doc.rust-lang.org/1.80.0/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>&lt;'_&gt;) -&gt; <a class="type" href="https://doc.rust-lang.org/1.80.0/core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></h4></section></summary><div class='docblock'>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-Deref-for-Error" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#572-578">source</a><a href="#impl-Deref-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/ops/deref/trait.Deref.html" title="trait core::ops::deref::Deref">Deref</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Target" class="associatedtype trait-impl"><a href="#associatedtype.Target" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.80.0/core/ops/deref/trait.Deref.html#associatedtype.Target" class="associatedtype">Target</a> = dyn <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">Error</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a></h4></section></summary><div class='docblock'>The resulting type after dereferencing.</div></details><details class="toggle method-toggle" open><summary><section id="method.deref" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#575-577">source</a><a href="#method.deref" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/ops/deref/trait.Deref.html#tymethod.deref" class="fn">deref</a>(&amp;self) -&gt; &amp;Self::<a class="associatedtype" href="https://doc.rust-lang.org/1.80.0/core/ops/deref/trait.Deref.html#associatedtype.Target" title="type core::ops::deref::Deref::Target">Target</a></h4></section></summary><div class='docblock'>Dereferences the value.</div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-DerefMut-for-Error" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#582-586">source</a><a href="#impl-DerefMut-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/ops/deref/trait.DerefMut.html" title="trait core::ops::deref::DerefMut">DerefMut</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.deref_mut" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#583-585">source</a><a href="#method.deref_mut" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/ops/deref/trait.DerefMut.html#tymethod.deref_mut" class="fn">deref_mut</a>(&amp;mut self) -&gt; &amp;mut Self::<a class="associatedtype" href="https://doc.rust-lang.org/1.80.0/core/ops/deref/trait.Deref.html#associatedtype.Target" title="type core::ops::deref::Deref::Target">Target</a></h4></section></summary><div class='docblock'>Mutably dereferences the value.</div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-Display-for-Error" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#588-592">source</a><a href="#impl-Display-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html" title="trait core::fmt::Display">Display</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.fmt-1" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#589-591">source</a><a href="#method.fmt-1" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html#tymethod.fmt" class="fn">fmt</a>(&amp;self, formatter: &amp;mut <a class="struct" href="https://doc.rust-lang.org/1.80.0/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>&lt;'_&gt;) -&gt; <a class="type" href="https://doc.rust-lang.org/1.80.0/core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></h4></section></summary><div class='docblock'>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html#tymethod.fmt">Read more</a></div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-Drop-for-Error" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#600-607">source</a><a href="#impl-Drop-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/ops/drop/trait.Drop.html" title="trait core::ops::drop::Drop">Drop</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.drop" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#601-606">source</a><a href="#method.drop" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/ops/drop/trait.Drop.html#tymethod.drop" class="fn">drop</a>(&amp;mut self)</h4></section></summary><div class='docblock'>Executes the destructor for this type. <a href="https://doc.rust-lang.org/1.80.0/core/ops/drop/trait.Drop.html#tymethod.drop">Read more</a></div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-From%3CE%3E-for-Error" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#559-568">source</a><a href="#impl-From%3CE%3E-for-Error" class="anchor">§</a><h3 class="code-header">impl&lt;E&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;E&gt; for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a><div class="where">where
E: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">StdError</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + 'static,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from-2" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#564-567">source</a><a href="#method.from-2" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(error: E) -&gt; Self</h4></section></summary><div class='docblock'>Converts to this type from the input type.</div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-From%3CError%3E-for-Box%3Cdyn+Error%3E" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#1006-1010">source</a><a href="#impl-From%3CError%3E-for-Box%3Cdyn+Error%3E" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;<a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a>&gt; for <a class="struct" href="https://doc.rust-lang.org/1.80.0/alloc/boxed/struct.Box.html" title="struct alloc::boxed::Box">Box</a>&lt;dyn <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">StdError</a> + 'static&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#1007-1009">source</a><a href="#method.from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(error: <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a>) -&gt; Self</h4></section></summary><div class='docblock'>Converts to this type from the input type.</div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-From%3CError%3E-for-Box%3Cdyn+Error+%2B+Send%3E" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#1000-1004">source</a><a href="#impl-From%3CError%3E-for-Box%3Cdyn+Error+%2B+Send%3E" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;<a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a>&gt; for <a class="struct" href="https://doc.rust-lang.org/1.80.0/alloc/boxed/struct.Box.html" title="struct alloc::boxed::Box">Box</a>&lt;dyn <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">StdError</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + 'static&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from-3" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#1001-1003">source</a><a href="#method.from-3" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(error: <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a>) -&gt; Self</h4></section></summary><div class='docblock'>Converts to this type from the input type.</div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-From%3CError%3E-for-Box%3Cdyn+Error+%2B+Send+%2B+Sync%3E" class="impl"><a class="src rightside" href="../src/anyhow/error.rs.html#988-998">source</a><a href="#impl-From%3CError%3E-for-Box%3Cdyn+Error+%2B+Send+%2B+Sync%3E" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;<a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a>&gt; for <a class="struct" href="https://doc.rust-lang.org/1.80.0/alloc/boxed/struct.Box.html" title="struct alloc::boxed::Box">Box</a>&lt;dyn <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html" title="trait core::error::Error">StdError</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + 'static&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from-1" class="method trait-impl"><a class="src rightside" href="../src/anyhow/error.rs.html#990-997">source</a><a href="#method.from-1" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(error: <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a>) -&gt; Self</h4></section></summary><div class='docblock'>Converts to this type from the input type.</div></details></div></details></div><h2 id="synthetic-implementations" class="section-header">Auto Trait Implementations<a href="#synthetic-implementations" class="anchor">§</a></h2><div id="synthetic-implementations-list"><section id="impl-Freeze-for-Error" class="impl"><a href="#impl-Freeze-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Freeze.html" title="trait core::marker::Freeze">Freeze</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section><section id="impl-RefUnwindSafe-for-Error" class="impl"><a href="#impl-RefUnwindSafe-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section><section id="impl-Send-for-Error" class="impl"><a href="#impl-Send-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section><section id="impl-Sync-for-Error" class="impl"><a href="#impl-Sync-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section><section id="impl-Unpin-for-Error" class="impl"><a href="#impl-Unpin-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section><section id="impl-UnwindSafe-for-Error" class="impl"><a href="#impl-UnwindSafe-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/panic/unwind_safe/trait.UnwindSafe.html" title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a> for <a class="struct" href="struct.Error.html" title="struct anyhow::Error">Error</a></h3></section></div><h2 id="blanket-implementations" class="section-header">Blanket Implementations<a href="#blanket-implementations" class="anchor">§</a></h2><div id="blanket-implementations-list"><details class="toggle implementors-toggle"><summary><section id="impl-Any-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/any.rs.html#140">source</a><a href="#impl-Any-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/any/trait.Any.html" title="trait core::any::Any">Any</a> for T<div class="where">where
T: 'static + ?<a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.type_id" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/any.rs.html#141">source</a><a href="#method.type_id" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/any/trait.Any.html#tymethod.type_id" class="fn">type_id</a>(&amp;self) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.80.0/core/any/struct.TypeId.html" title="struct core::any::TypeId">TypeId</a></h4></section></summary><div class='docblock'>Gets the <code>TypeId</code> of <code>self</code>. <a href="https://doc.rust-lang.org/1.80.0/core/any/trait.Any.html#tymethod.type_id">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-Borrow%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/borrow.rs.html#208">source</a><a href="#impl-Borrow%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.Borrow.html" title="trait core::borrow::Borrow">Borrow</a>&lt;T&gt; for T<div class="where">where
T: ?<a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.borrow" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/borrow.rs.html#210">source</a><a href="#method.borrow" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.Borrow.html#tymethod.borrow" class="fn">borrow</a>(&amp;self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/std/primitive.reference.html">&amp;T</a></h4></section></summary><div class='docblock'>Immutably borrows from an owned value. <a href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.Borrow.html#tymethod.borrow">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-BorrowMut%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/borrow.rs.html#216">source</a><a href="#impl-BorrowMut%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.BorrowMut.html" title="trait core::borrow::BorrowMut">BorrowMut</a>&lt;T&gt; for T<div class="where">where
T: ?<a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.borrow_mut" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/borrow.rs.html#217">source</a><a href="#method.borrow_mut" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut" class="fn">borrow_mut</a>(&amp;mut self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/std/primitive.reference.html">&amp;mut T</a></h4></section></summary><div class='docblock'>Mutably borrows from an owned value. <a href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-From%3C!%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#782">source</a><a href="#impl-From%3C!%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/1.80.0/std/primitive.never.html">!</a>&gt; for T</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from-5" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#783">source</a><a href="#method.from-5" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(t: <a class="primitive" href="https://doc.rust-lang.org/1.80.0/std/primitive.never.html">!</a>) -&gt; T</h4></section></summary><div class='docblock'>Converts to this type from the input type.</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-From%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#765">source</a><a href="#impl-From%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt; for T</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from-4" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#768">source</a><a href="#method.from-4" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(t: T) -&gt; T</h4></section></summary><div class="docblock"><p>Returns the argument unchanged.</p>
</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-Into%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#748-750">source</a><a href="#impl-Into%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a>&lt;U&gt; for T<div class="where">where
U: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt;,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#758">source</a><a href="#method.into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.Into.html#tymethod.into" class="fn">into</a>(self) -&gt; U</h4></section></summary><div class="docblock"><p>Calls <code>U::from(self)</code>.</p>
<p>That is, this conversion is whatever the implementation of
<code><a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt; for U</code> chooses to do.</p>
</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-ToString-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/alloc/string.rs.html#2552">source</a><a href="#impl-ToString-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/alloc/string/trait.ToString.html" title="trait alloc::string::ToString">ToString</a> for T<div class="where">where
T: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html" title="trait core::fmt::Display">Display</a> + ?<a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.to_string" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/alloc/string.rs.html#2558">source</a><a href="#method.to_string" class="anchor">§</a><h4 class="code-header">default fn <a href="https://doc.rust-lang.org/1.80.0/alloc/string/trait.ToString.html#tymethod.to_string" class="fn">to_string</a>(&amp;self) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.80.0/alloc/string/struct.String.html" title="struct alloc::string::String">String</a></h4></section></summary><div class='docblock'>Converts the given value to a <code>String</code>. <a href="https://doc.rust-lang.org/1.80.0/alloc/string/trait.ToString.html#tymethod.to_string">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-TryFrom%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#805-807">source</a><a href="#impl-TryFrom%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;U&gt; for T<div class="where">where
U: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a>&lt;T&gt;,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Error" class="associatedtype trait-impl"><a href="#associatedtype.Error" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error" class="associatedtype">Error</a> = <a class="enum" href="https://doc.rust-lang.org/1.80.0/core/convert/enum.Infallible.html" title="enum core::convert::Infallible">Infallible</a></h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="toggle method-toggle" open><summary><section id="method.try_from" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#812">source</a><a href="#method.try_from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#tymethod.try_from" class="fn">try_from</a>(value: U) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.80.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;T, &lt;T as <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;U&gt;&gt;::<a class="associatedtype" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>&gt;</h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-TryInto%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#790-792">source</a><a href="#impl-TryInto%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryInto.html" title="trait core::convert::TryInto">TryInto</a>&lt;U&gt; for T<div class="where">where
U: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Error-1" class="associatedtype trait-impl"><a href="#associatedtype.Error-1" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryInto.html#associatedtype.Error" class="associatedtype">Error</a> = &lt;U as <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;&gt;::<a class="associatedtype" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a></h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="toggle method-toggle" open><summary><section id="method.try_into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#797">source</a><a href="#method.try_into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryInto.html#tymethod.try_into" class="fn">try_into</a>(self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.80.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;U, &lt;U as <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;&gt;::<a class="associatedtype" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>&gt;</h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details></div><script type="text/json" id="notable-traits-data">{"Chain<'_>":"<h3>Notable traits for <code><a class=\"struct\" href=\"struct.Chain.html\" title=\"struct anyhow::Chain\">Chain</a>&lt;'a&gt;</code></h3><pre><code><div class=\"where\">impl&lt;'a&gt; <a class=\"trait\" href=\"https://doc.rust-lang.org/1.80.0/core/iter/traits/iterator/trait.Iterator.html\" title=\"trait core::iter::traits::iterator::Iterator\">Iterator</a> for <a class=\"struct\" href=\"struct.Chain.html\" title=\"struct anyhow::Chain\">Chain</a>&lt;'a&gt;</div><div class=\"where\"> type <a href=\"https://doc.rust-lang.org/1.80.0/core/iter/traits/iterator/trait.Iterator.html#associatedtype.Item\" class=\"associatedtype\">Item</a> = &amp;'a (dyn <a class=\"trait\" href=\"https://doc.rust-lang.org/1.80.0/core/error/trait.Error.html\" title=\"trait core::error::Error\">StdError</a> + 'static);</div>"}</script></section></div></main></body></html>
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