macro.bitflags.html 14 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192
  1. <!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 `bitflags` macro in crate `bitflags`."><meta name="keywords" content="rust, rustlang, rust-lang, bitflags"><title>bitflags::bitflags - 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="../light.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">&#9776;</div><div class="sidebar-elems"><p class='location'><a href='index.html'>bitflags</a></p><script>window.sidebarCurrent = {name: 'bitflags', ty: 'macro', relpath: ''};</script><script defer src="sidebar-items.js"></script></div></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"><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='in-band'>Macro <a href='index.html'>bitflags</a>::<wbr><a class="macro" href=''>bitflags</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'>&#x2212;</span>]</a></span><a class='srclink' href='../src/bitflags/lib.rs.html#329-387' title='goto source code'>[src]</a></span></h1><div class="docblock type-decl"><pre class="rust macro">
  2. <span class="macro">macro_rules</span><span class="macro">!</span> <span class="ident">bitflags</span> {
  3. (
  4. $(<span class="attribute">#[<span class="macro-nonterminal">$</span><span class="macro-nonterminal">outer</span>:<span class="ident">meta</span>]</span>)<span class="op">*</span>
  5. <span class="kw">pub</span> <span class="kw">struct</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">BitFlags</span>:<span class="ident">ident</span>: <span class="macro-nonterminal">$</span><span class="macro-nonterminal">T</span>:<span class="ident">ty</span> {
  6. $(
  7. $(<span class="attribute">#[<span class="macro-nonterminal">$</span><span class="macro-nonterminal">inner</span>:<span class="ident">ident</span> $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">args</span>:<span class="ident">tt</span>)<span class="kw-2">*</span>]</span>)<span class="op">*</span>
  8. <span class="kw">const</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">Flag</span>:<span class="ident">ident</span> <span class="op">=</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">value</span>:<span class="ident">expr</span>;
  9. )<span class="op">+</span>
  10. }
  11. ) <span class="op">=&gt;</span> { ... };
  12. (
  13. $(<span class="attribute">#[<span class="macro-nonterminal">$</span><span class="macro-nonterminal">outer</span>:<span class="ident">meta</span>]</span>)<span class="op">*</span>
  14. <span class="kw">struct</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">BitFlags</span>:<span class="ident">ident</span>: <span class="macro-nonterminal">$</span><span class="macro-nonterminal">T</span>:<span class="ident">ty</span> {
  15. $(
  16. $(<span class="attribute">#[<span class="macro-nonterminal">$</span><span class="macro-nonterminal">inner</span>:<span class="ident">ident</span> $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">args</span>:<span class="ident">tt</span>)<span class="kw-2">*</span>]</span>)<span class="op">*</span>
  17. <span class="kw">const</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">Flag</span>:<span class="ident">ident</span> <span class="op">=</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">value</span>:<span class="ident">expr</span>;
  18. )<span class="op">+</span>
  19. }
  20. ) <span class="op">=&gt;</span> { ... };
  21. (
  22. $(<span class="attribute">#[<span class="macro-nonterminal">$</span><span class="macro-nonterminal">outer</span>:<span class="ident">meta</span>]</span>)<span class="op">*</span>
  23. <span class="kw">pub</span> ($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">vis</span>:<span class="ident">tt</span>)<span class="op">+</span>) <span class="kw">struct</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">BitFlags</span>:<span class="ident">ident</span>: <span class="macro-nonterminal">$</span><span class="macro-nonterminal">T</span>:<span class="ident">ty</span> {
  24. $(
  25. $(<span class="attribute">#[<span class="macro-nonterminal">$</span><span class="macro-nonterminal">inner</span>:<span class="ident">ident</span> $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">args</span>:<span class="ident">tt</span>)<span class="kw-2">*</span>]</span>)<span class="op">*</span>
  26. <span class="kw">const</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">Flag</span>:<span class="ident">ident</span> <span class="op">=</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">value</span>:<span class="ident">expr</span>;
  27. )<span class="op">+</span>
  28. }
  29. ) <span class="op">=&gt;</span> { ... };
  30. }</pre>
  31. </div><div class='docblock'><p>The macro used to generate the flag structure.</p>
  32. <p>See the <a href="../bitflags/index.html">crate level docs</a> for complete documentation.</p>
  33. <h1 id="example" class="section-header"><a href="#example">Example</a></h1>
  34. <pre class="rust rust-example-rendered">
  35. <span class="attribute">#[<span class="ident">macro_use</span>]</span>
  36. <span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">bitflags</span>;
  37. <span class="macro">bitflags</span><span class="macro">!</span> {
  38. <span class="kw">struct</span> <span class="ident">Flags</span>: <span class="ident">u32</span> {
  39. <span class="kw">const</span> <span class="ident">A</span> <span class="op">=</span> <span class="number">0b00000001</span>;
  40. <span class="kw">const</span> <span class="ident">B</span> <span class="op">=</span> <span class="number">0b00000010</span>;
  41. <span class="kw">const</span> <span class="ident">C</span> <span class="op">=</span> <span class="number">0b00000100</span>;
  42. <span class="kw">const</span> <span class="ident">ABC</span> <span class="op">=</span> <span class="self">Self</span>::<span class="ident">A</span>.<span class="ident">bits</span> <span class="op">|</span> <span class="self">Self</span>::<span class="ident">B</span>.<span class="ident">bits</span> <span class="op">|</span> <span class="self">Self</span>::<span class="ident">C</span>.<span class="ident">bits</span>;
  43. }
  44. }
  45. <span class="kw">fn</span> <span class="ident">main</span>() {
  46. <span class="kw">let</span> <span class="ident">e1</span> <span class="op">=</span> <span class="ident">Flags</span>::<span class="ident">A</span> <span class="op">|</span> <span class="ident">Flags</span>::<span class="ident">C</span>;
  47. <span class="kw">let</span> <span class="ident">e2</span> <span class="op">=</span> <span class="ident">Flags</span>::<span class="ident">B</span> <span class="op">|</span> <span class="ident">Flags</span>::<span class="ident">C</span>;
  48. <span class="macro">assert_eq</span><span class="macro">!</span>((<span class="ident">e1</span> <span class="op">|</span> <span class="ident">e2</span>), <span class="ident">Flags</span>::<span class="ident">ABC</span>); <span class="comment">// union</span>
  49. <span class="macro">assert_eq</span><span class="macro">!</span>((<span class="ident">e1</span> <span class="op">&amp;</span> <span class="ident">e2</span>), <span class="ident">Flags</span>::<span class="ident">C</span>); <span class="comment">// intersection</span>
  50. <span class="macro">assert_eq</span><span class="macro">!</span>((<span class="ident">e1</span> <span class="op">-</span> <span class="ident">e2</span>), <span class="ident">Flags</span>::<span class="ident">A</span>); <span class="comment">// set difference</span>
  51. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="op">!</span><span class="ident">e2</span>, <span class="ident">Flags</span>::<span class="ident">A</span>); <span class="comment">// set complement</span>
  52. }</pre>
  53. <p>The generated <code>struct</code>s can also be extended with type and trait
  54. implementations:</p>
  55. <pre class="rust rust-example-rendered">
  56. <span class="attribute">#[<span class="ident">macro_use</span>]</span>
  57. <span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">bitflags</span>;
  58. <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">fmt</span>;
  59. <span class="macro">bitflags</span><span class="macro">!</span> {
  60. <span class="kw">struct</span> <span class="ident">Flags</span>: <span class="ident">u32</span> {
  61. <span class="kw">const</span> <span class="ident">A</span> <span class="op">=</span> <span class="number">0b00000001</span>;
  62. <span class="kw">const</span> <span class="ident">B</span> <span class="op">=</span> <span class="number">0b00000010</span>;
  63. }
  64. }
  65. <span class="kw">impl</span> <span class="ident">Flags</span> {
  66. <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">clear</span>(<span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="self">self</span>) {
  67. <span class="self">self</span>.<span class="ident">bits</span> <span class="op">=</span> <span class="number">0</span>; <span class="comment">// The `bits` field can be accessed from within the</span>
  68. <span class="comment">// same module where the `bitflags!` macro was invoked.</span>
  69. }
  70. }
  71. <span class="kw">impl</span> <span class="ident">fmt</span>::<span class="ident">Display</span> <span class="kw">for</span> <span class="ident">Flags</span> {
  72. <span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">f</span>: <span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-&gt;</span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> {
  73. <span class="macro">write</span><span class="macro">!</span>(<span class="ident">f</span>, <span class="string">&quot;hi!&quot;</span>)
  74. }
  75. }
  76. <span class="kw">fn</span> <span class="ident">main</span>() {
  77. <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">flags</span> <span class="op">=</span> <span class="ident">Flags</span>::<span class="ident">A</span> <span class="op">|</span> <span class="ident">Flags</span>::<span class="ident">B</span>;
  78. <span class="ident">flags</span>.<span class="ident">clear</span>();
  79. <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">flags</span>.<span class="ident">is_empty</span>());
  80. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="macro">format</span><span class="macro">!</span>(<span class="string">&quot;{}&quot;</span>, <span class="ident">flags</span>), <span class="string">&quot;hi!&quot;</span>);
  81. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="macro">format</span><span class="macro">!</span>(<span class="string">&quot;{:?}&quot;</span>, <span class="ident">Flags</span>::<span class="ident">A</span> <span class="op">|</span> <span class="ident">Flags</span>::<span class="ident">B</span>), <span class="string">&quot;A | B&quot;</span>);
  82. <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="macro">format</span><span class="macro">!</span>(<span class="string">&quot;{:?}&quot;</span>, <span class="ident">Flags</span>::<span class="ident">B</span>), <span class="string">&quot;B&quot;</span>);
  83. }</pre>
  84. </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>&#9166;</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><p>Search multiple things at once by splitting your query with comma (e.g. <code>str,u8</code> or <code>String,struct:Vec,test</code>)</p></div></div></aside><script>window.rootPath = "../";window.currentCrate = "bitflags";</script><script src="../aliases.js"></script><script src="../main.js"></script><script defer src="../search-index.js"></script></body></html>