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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="Additional methods for `Ident` not provided by proc-macro2 or libproc_macro."><title>IdentExt in syn::ext - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceSerif4-Regular-46f98efaafac5295.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/FiraSans-Regular-018c141bf0843ffd.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/FiraSans-Medium-8f9a781e4970d388.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2"><link rel="stylesheet" href="../../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../../static.files/rustdoc-ac92e1bbe349e143.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="1.76.0 (07dca489a 2024-02-04)" data-channel="1.76.0" data-search-js="search-2b6ce74ff89ae146.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../../static.files/storage-f2adc0d6ca4d09fb.js"></script><script defer src="sidebar-items.js"></script><script defer src="../../static.files/main-305769736d49e732.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-feafe1bb7466e4bd.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-16x16-8b506e7a72182f1c.png"><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 trait"><!--[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">&#9776;</button></nav><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../syn/index.html">syn</a><span class="version">2.0.51</span></h2></div><h2 class="location"><a href="#">IdentExt</a></h2><div class="sidebar-elems"><section><h3><a href="#provided-associated-consts">Provided Associated Constants</a></h3><ul class="block"><li><a href="#associatedconstant.peek_any">peek_any</a></li></ul><h3><a href="#required-methods">Required Methods</a></h3><ul class="block"><li><a href="#tymethod.parse_any">parse_any</a></li><li><a href="#tymethod.unraw">unraw</a></li></ul><h3><a href="#object-safety">Object Safety</a></h3><h3><a href="#implementors">Implementors</a></h3></section><h2><a href="index.html">In syn::ext</a></h2></div></nav><div class="sidebar-resizer"></div>
<main><div class="width-limiter"><nav class="sub"><form class="search-form"><span></span><div id="sidebar-button" tabindex="-1"><a href="../../syn/all.html" title="show sidebar"></a></div><input class="search-input" name="search" aria-label="Run search in the documentation" autocomplete="off" spellcheck="false" placeholder="Click or press S to search, ? for more options…" type="search"><div id="help-button" tabindex="-1"><a href="../../help.html" title="help">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../static.files/wheel-7b819b6101059cd0.svg"></a></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1>Trait <a href="../index.html">syn</a>::<wbr><a href="index.html">ext</a>::<wbr><a class="trait" href="#">IdentExt</a><button id="copy-path" title="Copy item path to clipboard"><img src="../../static.files/clipboard-7571035ce49a181d.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="src" href="../../src/syn/ext.rs.html#15-84">source</a> · <button id="toggle-all-docs" title="collapse all docs">[<span>&#x2212;</span>]</button></span></div><pre class="rust item-decl"><code>pub trait IdentExt: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a> + Sealed {
const <a href="#associatedconstant.peek_any" class="constant">peek_any</a>: PeekFn = private::PeekFn;
// Required methods
fn <a href="#tymethod.parse_any" class="fn">parse_any</a>(input: <a class="type" href="../parse/type.ParseStream.html" title="type syn::parse::ParseStream">ParseStream</a>&lt;'_&gt;) -&gt; <a class="type" href="../parse/type.Result.html" title="type syn::parse::Result">Result</a>&lt;Self&gt;;
<span class="item-spacer"></span> fn <a href="#tymethod.unraw" class="fn">unraw</a>(&amp;self) -&gt; <a class="struct" href="../struct.Ident.html" title="struct syn::Ident">Ident</a>;
}</code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Additional methods for <code>Ident</code> not provided by proc-macro2 or libproc_macro.</p>
<p>This trait is sealed and cannot be implemented for types outside of Syn. It
is implemented only for <code>proc_macro2::Ident</code>.</p>
</div></details><h2 id="provided-associated-consts" class="section-header">Provided Associated Constants<a href="#provided-associated-consts" class="anchor">§</a></h2><div class="methods"><details class="toggle" open><summary><section id="associatedconstant.peek_any" class="method"><a class="src rightside" href="../../src/syn/ext.rs.html#54">source</a><h4 class="code-header">const <a href="#associatedconstant.peek_any" class="constant">peek_any</a>: PeekFn = private::PeekFn</h4></section></summary><div class="docblock"><p>Peeks any identifier including keywords. Usage:
<code>input.peek(Ident::peek_any)</code></p>
<p>This is different from <code>input.peek(Ident)</code> which only returns true in
the case of an ident which is not a Rust keyword.</p>
</div></details></div><h2 id="required-methods" class="section-header">Required Methods<a href="#required-methods" class="anchor">§</a></h2><div class="methods"><details class="toggle method-toggle" open><summary><section id="tymethod.parse_any" class="method"><a class="src rightside" href="../../src/syn/ext.rs.html#46">source</a><h4 class="code-header">fn <a href="#tymethod.parse_any" class="fn">parse_any</a>(input: <a class="type" href="../parse/type.ParseStream.html" title="type syn::parse::ParseStream">ParseStream</a>&lt;'_&gt;) -&gt; <a class="type" href="../parse/type.Result.html" title="type syn::parse::Result">Result</a>&lt;Self&gt;</h4></section></summary><div class="docblock"><p>Parses any identifier including keywords.</p>
<p>This is useful when parsing macro input which allows Rust keywords as
identifiers.</p>
<h5 id="example"><a href="#example">Example</a></h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>syn::{Error, Ident, <span class="prelude-ty">Result</span>, Token};
<span class="kw">use </span>syn::ext::IdentExt;
<span class="kw">use </span>syn::parse::ParseStream;
<span class="kw">mod </span>kw {
<span class="macro">syn::custom_keyword!</span>(name);
}
<span class="comment">// Parses input that looks like `name = NAME` where `NAME` can be
// any identifier.
//
// Examples:
//
// name = anything
// name = impl
</span><span class="kw">fn </span>parse_dsl(input: ParseStream) -&gt; <span class="prelude-ty">Result</span>&lt;Ident&gt; {
input.parse::&lt;kw::name&gt;()<span class="question-mark">?</span>;
input.parse::&lt;<span class="macro">Token!</span>[=]&gt;()<span class="question-mark">?</span>;
<span class="kw">let </span>name = input.call(Ident::parse_any)<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(name)
}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="tymethod.unraw" class="method"><a class="src rightside" href="../../src/syn/ext.rs.html#83">source</a><h4 class="code-header">fn <a href="#tymethod.unraw" class="fn">unraw</a>(&amp;self) -&gt; <a class="struct" href="../struct.Ident.html" title="struct syn::Ident">Ident</a></h4></section></summary><div class="docblock"><p>Strips the raw marker <code>r#</code>, if any, from the beginning of an ident.</p>
<ul>
<li>unraw(<code>x</code>) = <code>x</code></li>
<li>unraw(<code>move</code>) = <code>move</code></li>
<li>unraw(<code>r#move</code>) = <code>move</code></li>
</ul>
<h5 id="example-1"><a href="#example-1">Example</a></h5>
<p>In the case of interop with other languages like Python that have a
different set of keywords than Rust, we might come across macro input
that involves raw identifiers to refer to ordinary variables in the
other language with a name that happens to be a Rust keyword.</p>
<p>The function below appends an identifier from the callers input onto a
fixed prefix. Without using <code>unraw()</code>, this would tend to produce
invalid identifiers like <code>__pyo3_get_r#move</code>.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>proc_macro2::Span;
<span class="kw">use </span>syn::Ident;
<span class="kw">use </span>syn::ext::IdentExt;
<span class="kw">fn </span>ident_for_getter(variable: <span class="kw-2">&amp;</span>Ident) -&gt; Ident {
<span class="kw">let </span>getter = <span class="macro">format!</span>(<span class="string">"__pyo3_get_{}"</span>, variable.unraw());
Ident::new(<span class="kw-2">&amp;</span>getter, Span::call_site())
}</code></pre></div>
</div></details></div><h2 id="object-safety" class="section-header">Object Safety<a href="#object-safety" class="anchor">§</a></h2><div class="object-safety-info">This trait is <b>not</b> <a href="https://doc.rust-lang.org/1.76.0/reference/items/traits.html#object-safety">object safe</a>.</div><h2 id="implementors" class="section-header">Implementors<a href="#implementors" class="anchor">§</a></h2><div id="implementors-list"><section id="impl-IdentExt-for-Ident" class="impl"><a class="src rightside" href="../../src/syn/ext.rs.html#86-102">source</a><a href="#impl-IdentExt-for-Ident" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="trait.IdentExt.html" title="trait syn::ext::IdentExt">IdentExt</a> for <a class="struct" href="../struct.Ident.html" title="struct syn::Ident">Ident</a></h3></section></div><script src="../../trait.impl/syn/ext/trait.IdentExt.js" data-ignore-extern-crates="proc_macro2" async></script></section></div></main></body></html>