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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."><meta name="keywords" content="rust, rustlang, rust-lang, IdentExt"><title>IdentExt in syn::ext - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" type="text/css" href="../../normalize.css"><link rel="stylesheet" type="text/css" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../../ayu.css" disabled><link rel="stylesheet" type="text/css" href="../../dark.css" disabled><link rel="stylesheet" type="text/css" href="../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../storage.js"></script><script defer src="sidebar-items.js"></script><script defer src="../../main.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../favicon.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">☰</button><a class="sidebar-logo" href="../../syn/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a><h2 class="location"></h2></nav><nav class="sidebar"><a class="sidebar-logo" href="../../syn/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a><h2 class="location"><a href="#">IdentExt</a></h2><div class="sidebar-elems"><section><div class="block"><h3 class="sidebar-title"><a href="#provided-associated-consts">Provided Associated Constants</a></h3><ul><li><a href="#associatedconstant.peek_any">peek_any</a></li></ul></div><div class="block"><h3 class="sidebar-title"><a href="#required-methods">Required Methods</a></h3><ul><li><a href="#tymethod.parse_any">parse_any</a></li><li><a href="#tymethod.unraw">unraw</a></li></ul></div><div class="block"><h3 class="sidebar-title"><a href="#implementors">Implementors</a></h3></div></section><h2 class="location"><a href="index.html">In syn::ext</a></h2></div></nav><main><div class="width-limiter"><div class="sub-container"><a class="sub-logo-container" href="../../syn/index.html"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></a><nav class="sub"><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><button type="button">?</button></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav></div><section id="main-content" class="content"><div class="main-heading"><h1 class="fqn"><span class="in-band">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" onclick="copy_path(this)" title="Copy item path to clipboard"><img src="../../clipboard.svg" width="19" height="18" alt="Copy item path"></button></span></h1><span class="out-of-band"><a class="srclink" href="../../src/syn/ext.rs.html#18-87">source</a> · <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class="inner">−</span>]</a></span></div><div class="docblock item-decl"><pre class="rust trait"><code>pub trait IdentExt: <a class="trait" href="https://doc.rust-lang.org/1.64.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a> + Sealed {
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const <a href="#associatedconstant.peek_any" class="constant">peek_any</a>: PeekFn = private::PeekFn;
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fn <a href="#tymethod.parse_any" class="fnname">parse_any</a>(input: <a class="type" href="../parse/type.ParseStream.html" title="type syn::parse::ParseStream">ParseStream</a><'_>) -> <a class="type" href="../parse/type.Result.html" title="type syn::parse::Result">Result</a><Self>;
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<span class="item-spacer"></span> fn <a href="#tymethod.unraw" class="fnname">unraw</a>(&self) -> <a class="struct" href="../struct.Ident.html" title="struct syn::Ident">Ident</a>;
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}</code></pre></div><details class="rustdoc-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>
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<p>This trait is sealed and cannot be implemented for types outside of Syn. It
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is implemented only for <code>proc_macro2::Ident</code>.</p>
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<p><em>This trait is available only if Syn is built with the <code>"parsing"</code> feature.</em></p>
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</div></details><h2 id="provided-associated-consts" class="small-section-header">Provided Associated Constants<a href="#provided-associated-consts" class="anchor"></a></h2><div class="methods"><details class="rustdoc-toggle" open><summary><div id="associatedconstant.peek_any" class="method has-srclink"><div class="rightside"><a class="srclink" href="../../src/syn/ext.rs.html#57">source</a></div><h4 class="code-header">const <a href="#associatedconstant.peek_any" class="constant">peek_any</a>: PeekFn = private::PeekFn</h4></div></summary><div class="docblock"><p>Peeks any identifier including keywords. Usage:
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<code>input.peek(Ident::peek_any)</code></p>
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<p>This is different from <code>input.peek(Ident)</code> which only returns true in
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the case of an ident which is not a Rust keyword.</p>
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</div></details></div><h2 id="required-methods" class="small-section-header">Required Methods<a href="#required-methods" class="anchor"></a></h2><div class="methods"><details class="rustdoc-toggle" open><summary><div id="tymethod.parse_any" class="method has-srclink"><div class="rightside"><a class="srclink" href="../../src/syn/ext.rs.html#49">source</a></div><h4 class="code-header">fn <a href="#tymethod.parse_any" class="fnname">parse_any</a>(input: <a class="type" href="../parse/type.ParseStream.html" title="type syn::parse::ParseStream">ParseStream</a><'_>) -> <a class="type" href="../parse/type.Result.html" title="type syn::parse::Result">Result</a><Self></h4></div></summary><div class="docblock"><p>Parses any identifier including keywords.</p>
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<p>This is useful when parsing macro input which allows Rust keywords as
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identifiers.</p>
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<h5 id="example"><a href="#example">Example</a></h5>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use</span> <span class="ident">syn</span>::{<span class="ident">Error</span>, <span class="ident">Ident</span>, <span class="prelude-ty">Result</span>, <span class="ident">Token</span>};
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<span class="kw">use</span> <span class="ident">syn::ext::IdentExt</span>;
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<span class="kw">use</span> <span class="ident">syn::parse::ParseStream</span>;
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<span class="kw">mod</span> <span class="ident">kw</span> {
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<span class="macro">syn::custom_keyword!</span>(<span class="ident">name</span>);
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}
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<span class="comment">// Parses input that looks like `name = NAME` where `NAME` can be</span>
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<span class="comment">// any identifier.</span>
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<span class="comment">//</span>
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<span class="comment">// Examples:</span>
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<span class="comment">//</span>
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<span class="comment">// name = anything</span>
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<span class="comment">// name = impl</span>
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<span class="kw">fn</span> <span class="ident">parse_dsl</span>(<span class="ident">input</span>: <span class="ident">ParseStream</span>) -> <span class="prelude-ty">Result</span><span class="op"><</span><span class="ident">Ident</span><span class="op">></span> {
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<span class="ident">input</span>.<span class="ident">parse</span>::<span class="op"><</span><span class="ident">kw::name</span><span class="op">></span>()<span class="question-mark">?</span>;
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<span class="ident">input</span>.<span class="ident">parse</span>::<span class="op"><</span><span class="macro">Token!</span>[<span class="op">=</span>]<span class="op">></span>()<span class="question-mark">?</span>;
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<span class="kw">let</span> <span class="ident">name</span> <span class="op">=</span> <span class="ident">input</span>.<span class="ident">call</span>(<span class="ident">Ident::parse_any</span>)<span class="question-mark">?</span>;
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<span class="prelude-val">Ok</span>(<span class="ident">name</span>)
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}</code></pre></div>
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</div></details><details class="rustdoc-toggle" open><summary><div id="tymethod.unraw" class="method has-srclink"><div class="rightside"><a class="srclink" href="../../src/syn/ext.rs.html#86">source</a></div><h4 class="code-header">fn <a href="#tymethod.unraw" class="fnname">unraw</a>(&self) -> <a class="struct" href="../struct.Ident.html" title="struct syn::Ident">Ident</a></h4></div></summary><div class="docblock"><p>Strips the raw marker <code>r#</code>, if any, from the beginning of an ident.</p>
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<ul>
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<li>unraw(<code>x</code>) = <code>x</code></li>
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<li>unraw(<code>move</code>) = <code>move</code></li>
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<li>unraw(<code>r#move</code>) = <code>move</code></li>
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</ul>
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<h5 id="example-1"><a href="#example-1">Example</a></h5>
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<p>In the case of interop with other languages like Python that have a
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different set of keywords than Rust, we might come across macro input
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that involves raw identifiers to refer to ordinary variables in the
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other language with a name that happens to be a Rust keyword.</p>
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<p>The function below appends an identifier from the caller’s input onto a
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fixed prefix. Without using <code>unraw()</code>, this would tend to produce
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invalid identifiers like <code>__pyo3_get_r#move</code>.</p>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use</span> <span class="ident">proc_macro2::Span</span>;
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<span class="kw">use</span> <span class="ident">syn::Ident</span>;
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<span class="kw">use</span> <span class="ident">syn::ext::IdentExt</span>;
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<span class="kw">fn</span> <span class="ident">ident_for_getter</span>(<span class="ident">variable</span>: <span class="kw-2">&</span><span class="ident">Ident</span>) -> <span class="ident">Ident</span> {
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<span class="kw">let</span> <span class="ident">getter</span> <span class="op">=</span> <span class="macro">format!</span>(<span class="string">"__pyo3_get_{}"</span>, <span class="ident">variable</span>.<span class="ident">unraw</span>());
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<span class="ident">Ident::new</span>(<span class="kw-2">&</span><span class="ident">getter</span>, <span class="ident">Span::call_site</span>())
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}</code></pre></div>
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</div></details></div><h2 id="implementors" class="small-section-header">Implementors<a href="#implementors" class="anchor"></a></h2><div class="item-list" id="implementors-list"><section id="impl-IdentExt-for-Ident" class="impl has-srclink"><span class="rightside"><a class="srclink" href="../../src/syn/ext.rs.html#89-105">source</a></span><a href="#impl-IdentExt-for-Ident" class="anchor"></a><h3 class="code-header in-band">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 type="text/javascript" src="../../implementors/syn/ext/trait.IdentExt.js" data-ignore-extern-crates="proc_macro2" async></script></section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="syn" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.64.0 (a55dd71d5 2022-09-19)" ></div></body></html> |