website/api-docs/m_captcha/0.1.1/cfg_if/index.html
2021-03-15 17:12:26 +00:00

25 lines
No EOL
5.1 KiB
HTML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!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 `cfg_if` crate."><meta name="keywords" content="rust, rustlang, rust-lang, cfg_if"><title>cfg_if - 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">
<link rel="alternate icon" type="image/png" href="../favicon-16x16.png">
<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 mod"><!--[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='../cfg_if/index.html'><div class='logo-container rust-logo'><img src='../rust-logo.png' alt='logo'></div></a><p class="location">Crate cfg_if</p><div class="block version"><p>Version 1.0.0</p></div><div class="sidebar-elems"><a id="all-types" href="all.html"><p>See all cfg_if's items</p></a><div class="block items"><ul><li><a href="#macros">Macros</a></li></ul></div><p class="location"></p><script>window.sidebarCurrent = {name: "cfg_if", ty: "mod", relpath: "../"};</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><button type="button" class="help-button">?</button>
<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/cfg_if/lib.rs.html#1-176" title="goto source code">[src]</a></span><span class="in-band">Crate <a class="mod" href="">cfg_if</a></span></h1><div class="docblock"><p>A macro for defining <code>#[cfg]</code> if-else statements.</p>
<p>The macro provided by this crate, <code>cfg_if</code>, is similar to the <code>if/elif</code> C
preprocessor macro by allowing definition of a cascade of <code>#[cfg]</code> cases,
emitting the implementation which matches first.</p>
<p>This allows you to conveniently provide a long list <code>#[cfg]</code>'d blocks of code
without having to rewrite each clause multiple times.</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="ident">cfg_if</span>::<span class="macro">cfg_if</span><span class="macro">!</span> {
<span class="kw">if</span> <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">unix</span>)]</span> {
<span class="kw">fn</span> <span class="ident">foo</span>() { <span class="comment">/* unix specific functionality */</span> }
} <span class="kw">else</span> <span class="kw">if</span> <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_pointer_width</span> <span class="op">=</span> <span class="string">&quot;32&quot;</span>)]</span> {
<span class="kw">fn</span> <span class="ident">foo</span>() { <span class="comment">/* non-unix, 32-bit functionality */</span> }
} <span class="kw">else</span> {
<span class="kw">fn</span> <span class="ident">foo</span>() { <span class="comment">/* fallback implementation */</span> }
}
}
</pre></div>
</div><h2 id="macros" class="section-header"><a href="#macros">Macros</a></h2>
<table><tr class="module-item"><td><a class="macro" href="macro.cfg_if.html" title="cfg_if::cfg_if macro">cfg_if</a></td><td class="docblock-short"><p>The main macro provided by this crate. See crate documentation for more
information.</p>
</td></tr></table></section><section id="search" class="content hidden"></section><section class="footer"></section><script>window.rootPath = "../";window.currentCrate = "cfg_if";</script><script src="../main.js"></script><script defer src="../search-index.js"></script></body></html>