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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="Error returned when a Syn parser cannot parse the input tokens."><title>Error in syn::parse - 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="syn" 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="../../syn/index.html">syn</a><span class="version">2.0.72</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.combine">combine</a></li><li><a href="#method.into_compile_error">into_compile_error</a></li><li><a href="#method.new">new</a></li><li><a href="#method.new_spanned">new_spanned</a></li><li><a href="#method.span">span</a></li><li><a href="#method.to_compile_error">to_compile_error</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block trait-implementation"><li><a href="#impl-Clone-for-Error">Clone</a></li><li><a href="#impl-Debug-for-Error">Debug</a></li><li><a href="#impl-Display-for-Error">Display</a></li><li><a href="#impl-Error-for-Error">Error</a></li><li><a href="#impl-Extend%3CError%3E-for-Error">Extend&lt;Error&gt;</a></li><li><a href="#impl-From%3CLexError%3E-for-Error">From&lt;LexError&gt;</a></li><li><a href="#impl-IntoIterator-for-%26Error">IntoIterator</a></li><li><a href="#impl-IntoIterator-for-Error">IntoIterator</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%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-ToOwned-for-T">T
<h2 id="error-reporting-in-proc-macros"><a class="doc-anchor" href="#error-reporting-in-proc-macros">§</a>Error reporting in proc macros</h2>
<p>The correct way to report errors back to the compiler from a procedural
macro is by emitting an appropriately spanned invocation of
<a href="https://doc.rust-lang.org/1.80.0/core/macro.compile_error.html" title="macro core::compile_error"><code>compile_error!</code></a> in the generated code. This produces a better diagnostic
message than simply panicking the macro.</p>
<p>When parsing macro input, the <a href="../macro.parse_macro_input.html" title="macro syn::parse_macro_input"><code>parse_macro_input!</code></a> macro handles the
conversion to <code>compile_error!</code> automatically.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>proc_macro::TokenStream;
<span class="kw">use </span>syn::parse::{Parse, ParseStream, <span class="prelude-ty">Result</span>};
<span class="kw">use </span>syn::{parse_macro_input, ItemFn};
<span class="attr">#[proc_macro_attribute]
</span><span class="kw">pub fn </span>my_attr(args: TokenStream, input: TokenStream) -&gt; TokenStream {
<span class="kw">let </span>args = <span class="macro">parse_macro_input!</span>(args <span class="kw">as </span>MyAttrArgs);
<span class="kw">let </span>input = <span class="macro">parse_macro_input!</span>(input <span class="kw">as </span>ItemFn);
<span class="comment">/* ... */
</span>}
<span class="kw">struct </span>MyAttrArgs {
...
}
<span class="kw">impl </span>Parse <span class="kw">for </span>MyAttrArgs {
<span class="kw">fn </span>parse(input: ParseStream) -&gt; <span class="prelude-ty">Result</span>&lt;<span class="self">Self</span>&gt; {
...
}
}</code></pre></div>
<p>For errors that arise later than the initial parsing stage, the
<a href="struct.Error.html#method.to_compile_error" title="method syn::parse::Error::to_compile_error"><code>.to_compile_error()</code></a> or <a href="struct.Error.html#method.into_compile_error" title="method syn::parse::Error::into_compile_error"><code>.into_compile_error()</code></a> methods can be used to
perform an explicit conversion to <code>compile_error!</code>.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="attr">#[proc_macro_derive(MyDerive)]
</span><span class="kw">pub fn </span>my_derive(input: TokenStream) -&gt; TokenStream {
<span class="kw">let </span>input = <span class="macro">parse_macro_input!</span>(input <span class="kw">as </span>DeriveInput);
<span class="comment">// fn(DeriveInput) -&gt; syn::Result&lt;proc_macro2::TokenStream&gt;
</span>expand::my_derive(input)
.unwrap_or_else(syn::Error::into_compile_error)
.into()
}</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/syn/error.rs.html#127-273">source</a><a href="#impl-Error" class="anchor">§</a><h3 class="code-header">impl <a class="struct" href="struct.Error.html" title="struct syn::parse::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/syn/error.rs.html#158-172">source</a><h4 class="code-header">pub fn <a href="#method.new" class="fn">new</a>&lt;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>&gt;(span: <a class="struct" href="../../proc_macro2/struct.Span.html" title="struct proc_macro2::Span">Span</a>, message: T) -&gt; Self</h4></section></summary><div class="docblock"><p>Usually the <a href="struct.ParseBuffer.html#method.error" title="method syn::parse::ParseBuffer::error"><code>ParseStream::error</code></a> method will be used instead, which
automatically uses the correct span from the current position of the
parse stream.</p>
<p>Use <code>Error::new</code> when the error needs to be triggered on some span other
than where the parse stream is currently positioned.</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>syn::{Error, Ident, LitStr, <span class="prelude-ty">Result</span>, Token};
<span class="kw">use </span>syn::parse::ParseStream;
<span class="comment">// Parses input that looks like `name = "string"` where the key must be
// the identifier `name` and the value may be any string literal.
// Returns the string literal.
</span><span class="kw">fn </span>parse_name(input: ParseStream) -&gt; <span class="prelude-ty">Result</span>&lt;LitStr&gt; {
<span class="kw">let </span>name_token: Ident = input.parse()<span class="question-mark">?</span>;
<span class="kw">if </span>name_token != <span class="string">"name" </span>{
<span class="comment">// Trigger an error not on the current position of the stream,
// but on the position of the unexpected identifier.
</span><span class="kw">return </span><span class="prelude-val">Err</span>(Error::new(name_token.span(), <span class="string">"expected `name`"</span>));
}
input.parse::&lt;<span class="macro">Token!</span>[=]&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>s: LitStr = input.parse()<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(s)
}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.new_spanned" class="method"><a class="src rightside" href="../../src/syn/error.rs.html#189-203">source</a><h4 class="code-header">pub fn <a href="#method.new_spanned" class="fn">new_spanned</a>&lt;T: <a class="trait" href="../../quote/to_tokens/trait.ToTokens.html" title="trait quote::to_tokens::ToTokens">ToTokens</a>, U: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html" title="trait core::fmt::Display">Display</a>&gt;(tokens: T, message: U) -&gt; Self</h4></section></summary><div class="docblock"><p>Creates an error with the specified message spanning the given syntax
tree node.</p>
<p>Unlike the <code>Error::new</code> constructor, this constructor takes an argument
<code>tokens</code> which is a syntax tree node. This allows the resulting <code>Error</code>
to attempt to span all tokens inside of <code>tokens</code>. While you would
typically be able to use the <code>Spanned</code> trait with the above <code>Error::new</code>
constructor, implementation limitations today mean that
<code>Error::new_spanned</code> may provide a higher-quality error message on
stable Rust.</p>
<p>When in doubt its recommended to stick to <code>Error::new</code> (or
<code>ParseStream::error</code>)!</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.span" class="method"><a class="src rightside" href="../../src/syn/error.rs.html#210-216">source</a><h4 class="code-header">pub fn <a href="#method.span" class="fn">span</a>(&amp;self) -&gt; <a class="struct" href="../../proc_macro2/struct.Span.html" title="struct proc_macro2::Span">Span</a></h4></section></summary><div class="docblock"><p>The source location of the error.</p>
<p>Spans are not thread-safe so this function returns <code>Span::call_site()</code>
if called from a different thread than the one on which the <code>Error</code> was
originally created.</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.to_compile_error" class="method"><a class="src rightside" href="../../src/syn/error.rs.html#225-230">source</a><h4 class="code-header">pub fn <a href="#method.to_compile_error" class="fn">to_compile_error</a>(&amp;self) -&gt; <a class="struct" href="../../proc_macro2/struct.TokenStream.html" title="struct proc_macro2::TokenStream">TokenStream</a></h4></section></summary><div class="docblock"><p>Render the error as an invocation of <a href="https://doc.rust-lang.org/1.80.0/core/macro.compile_error.html" title="macro core::compile_error"><code>compile_error!</code></a>.</p>
<p>The <a href="../macro.parse_macro_input.html" title="macro syn::parse_macro_input"><code>parse_macro_input!</code></a> macro provides a convenient way to invoke
this method correctly in a procedural macro.</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.into_compile_error" class="method"><a class="src rightside" href="../../src/syn/error.rs.html#264-266">source</a><h4 class="code-header">pub fn <a href="#method.into_compile_error" class="fn">into_compile_error</a>(self) -&gt; <a class="struct" href="../../proc_macro2/struct.TokenStream.html" title="struct proc_macro2::TokenStream">TokenStream</a></h4></section></summary><div class="docblock"><p>Render the error as an invocation of <a href="https://doc.rust-lang.org/1.80.0/core/macro.compile_error.html" title="macro core::compile_error"><code>compile_error!</code></a>.</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="kw">use </span>proc_macro::TokenStream;
<span class="kw">use </span>syn::{parse_macro_input, DeriveInput, Error};
<span class="attr">#[proc_macro_derive(MyTrait)]
</span><span class="kw">pub fn </span>derive_my_trait(input: TokenStream) -&gt; TokenStream {
<span class="kw">let </span>input = <span class="macro">parse_macro_input!</span>(input <span class="kw">as </span>DeriveInput);
my_trait::expand(input)
.unwrap_or_else(Error::into_compile_error)
.into()
}
<span class="kw">mod </span>my_trait {
<span class="kw">use </span>proc_macro2::TokenStream;
<span class="kw">use </span>syn::{DeriveInput, <span class="prelude-ty">Result</span>};
<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>expand(input: DeriveInput) -&gt; <span class="prelude-ty">Result</span>&lt;TokenStream&gt; {
<span class="comment">/* ... */
</span>}
}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.combine" class="method"><a class="src rightside" href="../../src/syn/error.rs.html#270-272">source</a><h4 class="code-header">pub fn <a href="#method.combine" class="fn">combine</a>(&amp;mut self, another: <a class="struct" href="struct.Error.html" title="struct syn::parse::Error">Error</a>)</h4></section></summary><div class="docblock"><p>Add another error message to self such that when <code>to_compile_error()</code> is
called, both errors will be emitted together.</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-Clone-for-Error" class="impl"><a class="src rightside" href="../../src/syn/error.rs.html#378-384">source</a><a href="#impl-Clone-for-Error" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a> for <a class="struct" href="struct.Error.html" title="struct syn::parse::Error">Error</a></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.clone" class="method trait-impl"><a class="src rightside" href="../../src/syn/error.rs.html#379-383">source</a><a href="#method.clone" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/clone/trait.Clone.html#tymethod.clone" class="fn">clone</a>(&amp;self) -&gt; Self</h4></section></summary><div class='docblock'>Returns a copy of the value. <a href="https://doc.rust-lang.org/1.80.0/core/clone/trait.Clone.html#tymethod.clone">Read more</a></div></details><details class="toggle method-toggle" open><summary><section id="method.clone_from" class="method trait-impl"><span class="rightside"><span class="since" title="Stable since Rust version 1.0.0">1.0.0</span> · <a class="src" href="https://doc.rust-lang.org/1.80.0/src/core/clone.rs.html#169">source</a></span><a href="#method.clone_from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/clone/trait.Clone.html#method.clone_from" class="fn">clone_from</a>(&amp;mut self, source: <a class="primitive" href="https://doc.rust-lang.org/1.80.0/std/primitive.reference.html">&amp;Self</a>)</h4></section></summary><div class='docblock'>Performs copy-assignment from <code>source</code>. <a href="https://doc.rust-lang.org/1.80.0/core/clone/trait.Clone.html#method.clone_from">Read more</a></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/syn/error.rs.html#350-364">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 syn::parse::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/syn/error.rs.html#351-363">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.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-Display-for-Error" class="impl"><a class="src rightside" href="../../src/syn/error.rs.html#372-376">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 syn::parse::Error">Error</a></h3></section></s
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%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-1" 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-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>(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-ToOwned-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/alloc/borrow.rs.html#83-85">source</a><a href="#impl-ToOwned-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/borrow/trait.ToOwned.html" title="trait alloc::borrow::ToOwned">ToOwned</a> for T<div class="where">where
T: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Owned" class="associatedtype trait-impl"><a href="#associatedtype.Owned" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html#associatedtype.Owned" class="associatedtype">Owned</a> = T</h4></section></summary><div class='docblock'>The resulting type after obtaining ownership.</div></details><details class="toggle method-toggle" open><summary><section id="method.to_owned" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/alloc/borrow.rs.html#88">source</a><a href="#method.to_owned" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html#tymethod.to_owned" class="fn">to_owned</a>(&amp;self) -&gt; T</h4></section></summary><div class='docblock'>Creates owned data from borrowed data, usually by cloning. <a href="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html#tymethod.to_owned">Read more</a></div></details><details class="toggle method-toggle" open><summary><section id="method.clone_into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/alloc/borrow.rs.html#92">source</a><a href="#method.clone_into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html#method.clone_into" class="fn">clone_into</a>(&amp;self, target: <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'>Uses borrowed data to replace owned data, usually by cloning. <a href="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html#method.clone_into">Read more</a></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></section></div></main></body></html>