153 lines
6.8 KiB
HTML
153 lines
6.8 KiB
HTML
|
<!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 `parens` macro in crate `syn`.">
|
|||
|
|
<meta name="keywords" content="rust, rustlang, rust-lang, parens">
|
|||
|
|
|
|||
|
|
<title>syn::parens - 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="../dark.css">
|
|||
|
|
<link rel="stylesheet" type="text/css" href="../main.css" id="themeStyle">
|
|||
|
|
<script src="../storage.js"></script>
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
</head>
|
|||
|
|
<body class="rustdoc macro">
|
|||
|
|
<!--[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">☰</div>
|
|||
|
|
|
|||
|
|
<p class='location'><a href='index.html'>syn</a></p><script>window.sidebarCurrent = {name: 'parens', ty: 'macro', relpath: ''};</script><script defer src="sidebar-items.js"></script>
|
|||
|
|
</nav>
|
|||
|
|
|
|||
|
|
<div class="theme-picker">
|
|||
|
|
<button id="theme-picker" aria-label="Pick another theme!">
|
|||
|
|
<img src="../brush.svg" width="18" alt="Pick another theme!">
|
|||
|
|
</button>
|
|||
|
|
<div id="theme-choices"></div>
|
|||
|
|
</div>
|
|||
|
|
<script src="../theme.js"></script>
|
|||
|
|
<nav class="sub">
|
|||
|
|
<form class="search-form js-only">
|
|||
|
|
<div class="search-container">
|
|||
|
|
<input class="search-input" name="search"
|
|||
|
|
autocomplete="off"
|
|||
|
|
placeholder="Click or press ‘S’ to search, ‘?’ for more options…"
|
|||
|
|
type="search">
|
|||
|
|
</div>
|
|||
|
|
</form>
|
|||
|
|
</nav>
|
|||
|
|
|
|||
|
|
<section id='main' class="content">
|
|||
|
|
<h1 class='fqn'><span class='in-band'>Macro <a href='index.html'>syn</a>::<wbr><a class="macro" href=''>parens</a></span><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'>−</span>]
|
|||
|
|
</a>
|
|||
|
|
</span><a class='srclink' href='../src/syn/parsers.rs.html#1335-1343' title='goto source code'>[src]</a></span></h1>
|
|||
|
|
<pre class="rust macro">
|
|||
|
|
<span class="macro">macro_rules</span><span class="macro">!</span> <span class="ident">parens</span> {
|
|||
|
|
(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span>:<span class="ident">expr</span>, <span class="macro-nonterminal">$</span><span class="macro-nonterminal">submac</span>:<span class="macro">ident</span><span class="macro">!</span>( $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">args</span>:<span class="ident">tt</span>)<span class="op">*</span> )) <span class="op">=></span> { ... };
|
|||
|
|
(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span>:<span class="ident">expr</span>, <span class="macro-nonterminal">$</span><span class="macro-nonterminal">f</span>:<span class="ident">expr</span>) <span class="op">=></span> { ... };
|
|||
|
|
}</pre>
|
|||
|
|
<div class='docblock'><p>Parse inside of <code>(</code> <code>)</code> parentheses.</p>
|
|||
|
|
<p>This macro parses a set of balanced parentheses and invokes a sub-parser on
|
|||
|
|
the content inside. The sub-parser is required to consume all tokens within
|
|||
|
|
the parentheses in order for this parser to return successfully.</p>
|
|||
|
|
<ul>
|
|||
|
|
<li><strong>Syntax:</strong> <code>parens!(CONTENT)</code></li>
|
|||
|
|
<li><strong>Output:</strong> <code>(token::Paren, CONTENT)</code></li>
|
|||
|
|
</ul>
|
|||
|
|
|
|||
|
|
<pre class="rust rust-example-rendered">
|
|||
|
|
<span class="attribute">#[<span class="ident">macro_use</span>]</span>
|
|||
|
|
<span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">syn</span>;
|
|||
|
|
|
|||
|
|
<span class="kw">use</span> <span class="ident">syn</span>::<span class="ident">Expr</span>;
|
|||
|
|
<span class="kw">use</span> <span class="ident">syn</span>::<span class="ident">token</span>::<span class="ident">Paren</span>;
|
|||
|
|
|
|||
|
|
<span class="doccomment">/// Parses an expression inside of parentheses.</span>
|
|||
|
|
<span class="doccomment">///</span>
|
|||
|
|
<span class="doccomment">/// Example: `(1 + 1)`</span>
|
|||
|
|
<span class="macro">named</span><span class="macro">!</span>(<span class="ident">expr_paren</span> <span class="op">-></span> (<span class="ident">Paren</span>, <span class="ident">Expr</span>), <span class="macro">parens</span><span class="macro">!</span>(<span class="macro">syn</span><span class="macro">!</span>(<span class="ident">Expr</span>)));</pre>
|
|||
|
|
<p><em>This macro is available if Syn is built with the <code>"parsing"</code> feature.</em></p>
|
|||
|
|
</div></section>
|
|||
|
|
<section id='search' class="content hidden"></section>
|
|||
|
|
|
|||
|
|
<section class="footer"></section>
|
|||
|
|
|
|||
|
|
<aside id="help" class="hidden">
|
|||
|
|
<div>
|
|||
|
|
<h1 class="hidden">Help</h1>
|
|||
|
|
|
|||
|
|
<div class="shortcuts">
|
|||
|
|
<h2>Keyboard Shortcuts</h2>
|
|||
|
|
|
|||
|
|
<dl>
|
|||
|
|
<dt><kbd>?</kbd></dt>
|
|||
|
|
<dd>Show this help dialog</dd>
|
|||
|
|
<dt><kbd>S</kbd></dt>
|
|||
|
|
<dd>Focus the search field</dd>
|
|||
|
|
<dt><kbd>↑</kbd></dt>
|
|||
|
|
<dd>Move up in search results</dd>
|
|||
|
|
<dt><kbd>↓</kbd></dt>
|
|||
|
|
<dd>Move down in search results</dd>
|
|||
|
|
<dt><kbd>↹</kbd></dt>
|
|||
|
|
<dd>Switch tab</dd>
|
|||
|
|
<dt><kbd>⏎</kbd></dt>
|
|||
|
|
<dd>Go to active search result</dd>
|
|||
|
|
<dt><kbd>+</kbd></dt>
|
|||
|
|
<dd>Expand all sections</dd>
|
|||
|
|
<dt><kbd>-</kbd></dt>
|
|||
|
|
<dd>Collapse all sections</dd>
|
|||
|
|
</dl>
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
<div class="infos">
|
|||
|
|
<h2>Search Tricks</h2>
|
|||
|
|
|
|||
|
|
<p>
|
|||
|
|
Prefix searches with a type followed by a colon (e.g.
|
|||
|
|
<code>fn:</code>) to restrict the search to a given type.
|
|||
|
|
</p>
|
|||
|
|
|
|||
|
|
<p>
|
|||
|
|
Accepted types are: <code>fn</code>, <code>mod</code>,
|
|||
|
|
<code>struct</code>, <code>enum</code>,
|
|||
|
|
<code>trait</code>, <code>type</code>, <code>macro</code>,
|
|||
|
|
and <code>const</code>.
|
|||
|
|
</p>
|
|||
|
|
|
|||
|
|
<p>
|
|||
|
|
Search functions by type signature (e.g.
|
|||
|
|
<code>vec -> usize</code> or <code>* -> vec</code>)
|
|||
|
|
</p>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</aside>
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
<script>
|
|||
|
|
window.rootPath = "../";
|
|||
|
|
window.currentCrate = "syn";
|
|||
|
|
</script>
|
|||
|
|
<script src="../main.js"></script>
|
|||
|
|
<script defer src="../search-index.js"></script>
|
|||
|
|
</body>
|
|||
|
|
</html>
|