mcquery-rs/doc/syn/ext/trait.IdentExt.html

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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="API documentation for the Rust `IdentExt` trait in crate `syn`."><meta name="keywords" content="rust, rustlang, rust-lang, IdentExt"><title>syn::ext::IdentExt - Rust</title><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="../../light.css" id="themeStyle"><link rel="stylesheet" type="text/css" href="../../dark.css" disabled ><link rel="stylesheet" type="text/css" href="../../ayu.css" disabled ><script id="default-settings"></script><script src="../../storage.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="icon" type="image/svg+xml" href="../../favicon.svg">
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<link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><style type="text/css">#crate-search{background-image:url("../../down-arrow.svg");}</style></head><body class="rustdoc trait"><!--[if lte IE 8]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="sidebar-menu">&#9776;</div><a href='../../syn/index.html'><div class='logo-container rust-logo'><img src='../../rust-logo.png' alt='logo'></div></a><p class="location">Trait IdentExt</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#associated-const">Associated Constants</a><div class="sidebar-links"><a href="#associatedconstant.peek_any">peek_any</a></div><a class="sidebar-title" href="#required-methods">Required Methods</a><div class="sidebar-links"><a href="#tymethod.parse_any">parse_any</a><a href="#tymethod.unraw">unraw</a></div><a class="sidebar-title" href="#implementors">Implementors</a></div><p class="location"><a href="../index.html">syn</a>::<wbr><a href="index.html">ext</a></p><script>window.sidebarCurrent = {name: "IdentExt", ty: "trait", relpath: ""};</script><script defer src="sidebar-items.js"></script></div></nav><div class="theme-picker"><button id="theme-picker" aria-label="Pick another theme!" aria-haspopup="menu"><img src="../../brush.svg" width="18" alt="Pick another theme!"></button><div id="theme-choices" role="menu"></div></div><script src="../../theme.js"></script><nav class="sub"><form class="search-form"><div class="search-container"><div><select id="crate-search"><option value="All crates">All crates</option></select><input class="search-input" name="search" disabled autocomplete="off" spellcheck="false" placeholder="Click or press S to search, ? for more options…" type="search"></div><span class="help-button">?</span>
<a id="settings-menu" href="../../settings.html"><img src="../../wheel.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><h1 class="fqn"><span class="out-of-band"><span id="render-detail"><a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class="inner">&#x2212;</span>]</a></span><a class="srclink" href="../../src/syn/ext.rs.html#18-87" title="goto source code">[src]</a></span><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></span></h1><div class="docblock type-decl hidden-by-usual-hider"><pre class="rust trait">pub trait IdentExt: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a> + Sealed {
const <a href="#associatedconstant.peek_any" class="constant"><b>peek_any</b></a>: PeekFn;
fn <a href="#tymethod.parse_any" class="fnname">parse_any</a>(input: <a class="type" href="../../syn/parse/type.ParseStream.html" title="type syn::parse::ParseStream">ParseStream</a>&lt;'_&gt;) -&gt; <a class="type" href="../../syn/parse/type.Result.html" title="type syn::parse::Result">Result</a>&lt;Self&gt;;
<div class="item-spacer"></div> fn <a href="#tymethod.unraw" class="fnname">unraw</a>(&amp;self) -&gt; <a class="struct" href="../../syn/struct.Ident.html" title="struct syn::Ident">Ident</a>;
}</pre></div><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>
<p><em>This trait is available only if Syn is built with the <code>&quot;parsing&quot;</code> feature.</em></p>
</div><h2 id="associated-const" class="small-section-header">Associated Constants<a href="#associated-const" class="anchor"></a></h2><div class="methods"><h3 id="associatedconstant.peek_any" class="method"><code>const <a href="#associatedconstant.peek_any" class="constant"><b>peek_any</b></a>: PeekFn</code></h3><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></div><span class="loading-content">Loading content...</span><h2 id="required-methods" class="small-section-header">Required methods<a href="#required-methods" class="anchor"></a></h2><div class="methods"><h3 id="tymethod.parse_any" class="method"><code>fn <a href="#tymethod.parse_any" class="fnname">parse_any</a>(input: <a class="type" href="../../syn/parse/type.ParseStream.html" title="type syn::parse::ParseStream">ParseStream</a>&lt;'_&gt;) -&gt; <a class="type" href="../../syn/parse/type.Result.html" title="type syn::parse::Result">Result</a>&lt;Self&gt;</code></h3><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>
<h1 id="example" class="section-header"><a href="#example">Example</a></h1>
<div class="example-wrap"><pre class="rust rust-example-rendered">
<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>};
<span class="kw">use</span> <span class="ident">syn</span>::<span class="ident">ext</span>::<span class="ident">IdentExt</span>;
<span class="kw">use</span> <span class="ident">syn</span>::<span class="ident">parse</span>::<span class="ident">ParseStream</span>;
<span class="kw">mod</span> <span class="ident">kw</span> {
<span class="ident">syn</span>::<span class="macro">custom_keyword</span><span class="macro">!</span>(<span class="ident">name</span>);
}
<span class="comment">// Parses input that looks like `name = NAME` where `NAME` can be</span>
<span class="comment">// any identifier.</span>
<span class="comment">//</span>
<span class="comment">// Examples:</span>
<span class="comment">//</span>
<span class="comment">// name = anything</span>
<span class="comment">// name = impl</span>
<span class="kw">fn</span> <span class="ident">parse_dsl</span>(<span class="ident">input</span>: <span class="ident">ParseStream</span>) <span class="op">-</span><span class="op">&gt;</span> <span class="prelude-ty">Result</span><span class="op">&lt;</span><span class="ident">Ident</span><span class="op">&gt;</span> {
<span class="ident">input</span>.<span class="ident">parse</span>::<span class="op">&lt;</span><span class="ident">kw</span>::<span class="ident">name</span><span class="op">&gt;</span>()<span class="question-mark">?</span>;
<span class="ident">input</span>.<span class="ident">parse</span>::<span class="op">&lt;</span><span class="macro">Token</span><span class="macro">!</span>[<span class="op">=</span>]<span class="op">&gt;</span>()<span class="question-mark">?</span>;
<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</span>::<span class="ident">parse_any</span>)<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(<span class="ident">name</span>)
}</pre></div>
</div><h3 id="tymethod.unraw" class="method"><code>fn <a href="#tymethod.unraw" class="fnname">unraw</a>(&amp;self) -&gt; <a class="struct" href="../../syn/struct.Ident.html" title="struct syn::Ident">Ident</a></code></h3><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>
<h1 id="example-1" class="section-header"><a href="#example-1">Example</a></h1>
<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 caller's 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">
<span class="kw">use</span> <span class="ident">proc_macro2</span>::<span class="ident">Span</span>;
<span class="kw">use</span> <span class="ident">syn</span>::<span class="ident">Ident</span>;
<span class="kw">use</span> <span class="ident">syn</span>::<span class="ident">ext</span>::<span class="ident">IdentExt</span>;
<span class="kw">fn</span> <span class="ident">ident_for_getter</span>(<span class="ident">variable</span>: <span class="kw-2">&amp;</span><span class="ident">Ident</span>) <span class="op">-</span><span class="op">&gt;</span> <span class="ident">Ident</span> {
<span class="kw">let</span> <span class="ident">getter</span> <span class="op">=</span> <span class="macro">format</span><span class="macro">!</span>(<span class="string">&quot;__pyo3_get_{}&quot;</span>, <span class="ident">variable</span>.<span class="ident">unraw</span>());
<span class="ident">Ident</span>::<span class="ident">new</span>(<span class="kw-2">&amp;</span><span class="ident">getter</span>, <span class="ident">Span</span>::<span class="ident">call_site</span>())
}</pre></div>
</div></div><span class="loading-content">Loading content...</span><h2 id="implementors" class="small-section-header">Implementors<a href="#implementors" class="anchor"></a></h2><div class="item-list" id="implementors-list"><h3 id="impl-IdentExt" class="impl"><code class="in-band">impl IdentExt for <a class="struct" href="../../syn/struct.Ident.html" title="struct syn::Ident">Ident</a></code><a href="#impl-IdentExt" class="anchor"></a><a class="srclink" href="../../src/syn/ext.rs.html#89-105" title="goto source code">[src]</a></h3><div class="impl-items"><h4 id="method.parse_any" class="method hidden"><code>fn <a href="#method.parse_any" class="fnname">parse_any</a>(input: <a class="type" href="../../syn/parse/type.ParseStream.html" title="type syn::parse::ParseStream">ParseStream</a>&lt;'_&gt;) -&gt; <a class="type" href="../../syn/parse/type.Result.html" title="type syn::parse::Result">Result</a>&lt;Self&gt;</code><a class="srclink" href="../../src/syn/ext.rs.html#90-95" title="goto source code">[src]</a></h4><h4 id="method.unraw" class="method hidden"><code>fn <a href="#method.unraw" class="fnname">unraw</a>(&amp;self) -&gt; <a class="struct" href="../../syn/struct.Ident.html" title="struct syn::Ident">Ident</a></code><a class="srclink" href="../../src/syn/ext.rs.html#97-104" title="goto source code">[src]</a></h4></div></div><span class="loading-content">Loading content...</span><script type="text/javascript" src="../../implementors/syn/ext/trait.IdentExt.js" async></script></section><section id="search" class="content hidden"></section><section class="footer"></section><script>window.rootPath = "../../";window.currentCrate = "syn";</script><script src="../../main.js"></script><script defer src="../../search-index.js"></script></body></html>