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diff --git a/src/lazy_static/lib.rs.html b/src/lazy_static/lib.rs.html new file mode 100644 index 0000000..b6e5e1e --- /dev/null +++ b/src/lazy_static/lib.rs.html @@ -0,0 +1,345 @@ +<!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="Source to the Rust file `/home/travis/.cargo/registry/src/github.com-0a35038f75765ae4/lazy_static-0.1.11/src/lib.rs`."> + <meta name="keywords" content="rust, rustlang, rust-lang"> + + <title>lib.rs.html -- source</title> + + <link rel="stylesheet" type="text/css" href="../../main.css"> + + + +</head> +<body class="rustdoc"> + <!--[if lte IE 8]> + <div class="warning"> + This old browser is unsupported and will most likely display funky + things. + </div> + <![endif]--> + + + + <section class="sidebar"> + + + </section> + + <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 source"><pre class="line-numbers"><span id="1"> 1</span> +<span id="2"> 2</span> +<span id="3"> 3</span> +<span id="4"> 4</span> +<span id="5"> 5</span> +<span id="6"> 6</span> +<span id="7"> 7</span> +<span id="8"> 8</span> +<span id="9"> 9</span> +<span id="10"> 10</span> +<span id="11"> 11</span> +<span id="12"> 12</span> +<span id="13"> 13</span> +<span id="14"> 14</span> +<span id="15"> 15</span> +<span id="16"> 16</span> +<span id="17"> 17</span> +<span id="18"> 18</span> +<span id="19"> 19</span> +<span id="20"> 20</span> +<span id="21"> 21</span> +<span id="22"> 22</span> +<span id="23"> 23</span> +<span id="24"> 24</span> +<span id="25"> 25</span> +<span id="26"> 26</span> +<span id="27"> 27</span> +<span id="28"> 28</span> +<span id="29"> 29</span> +<span id="30"> 30</span> +<span id="31"> 31</span> +<span id="32"> 32</span> +<span id="33"> 33</span> +<span id="34"> 34</span> +<span id="35"> 35</span> +<span id="36"> 36</span> +<span id="37"> 37</span> +<span id="38"> 38</span> +<span id="39"> 39</span> +<span id="40"> 40</span> +<span id="41"> 41</span> +<span id="42"> 42</span> +<span id="43"> 43</span> +<span id="44"> 44</span> +<span id="45"> 45</span> +<span id="46"> 46</span> +<span id="47"> 47</span> +<span id="48"> 48</span> +<span id="49"> 49</span> +<span id="50"> 50</span> +<span id="51"> 51</span> +<span id="52"> 52</span> +<span id="53"> 53</span> +<span id="54"> 54</span> +<span id="55"> 55</span> +<span id="56"> 56</span> +<span id="57"> 57</span> +<span id="58"> 58</span> +<span id="59"> 59</span> +<span id="60"> 60</span> +<span id="61"> 61</span> +<span id="62"> 62</span> +<span id="63"> 63</span> +<span id="64"> 64</span> +<span id="65"> 65</span> +<span id="66"> 66</span> +<span id="67"> 67</span> +<span id="68"> 68</span> +<span id="69"> 69</span> +<span id="70"> 70</span> +<span id="71"> 71</span> +<span id="72"> 72</span> +<span id="73"> 73</span> +<span id="74"> 74</span> +<span id="75"> 75</span> +<span id="76"> 76</span> +<span id="77"> 77</span> +<span id="78"> 78</span> +<span id="79"> 79</span> +<span id="80"> 80</span> +<span id="81"> 81</span> +<span id="82"> 82</span> +<span id="83"> 83</span> +<span id="84"> 84</span> +<span id="85"> 85</span> +<span id="86"> 86</span> +<span id="87"> 87</span> +<span id="88"> 88</span> +<span id="89"> 89</span> +<span id="90"> 90</span> +<span id="91"> 91</span> +<span id="92"> 92</span> +<span id="93"> 93</span> +<span id="94"> 94</span> +<span id="95"> 95</span> +<span id="96"> 96</span> +<span id="97"> 97</span> +<span id="98"> 98</span> +<span id="99"> 99</span> +<span id="100">100</span> +<span id="101">101</span> +<span id="102">102</span> +<span id="103">103</span> +<span id="104">104</span> +<span id="105">105</span> +<span id="106">106</span> +<span id="107">107</span> +<span id="108">108</span> +<span id="109">109</span> +<span id="110">110</span> +<span id="111">111</span> +<span id="112">112</span> +<span id="113">113</span> +<span id="114">114</span> +<span id="115">115</span> +<span id="116">116</span> +<span id="117">117</span> +<span id="118">118</span> +<span id="119">119</span> +<span id="120">120</span> +<span id="121">121</span> +<span id="122">122</span> +<span id="123">123</span> +<span id="124">124</span> +</pre><pre class='rust '> +<span class='doccomment'>/*! +A macro for declaring lazily evaluated statics. + +Using this macro, it is possible to have `static`s that require code to be +executed at runtime in order to be initialized. +This includes anything requiring heap allocations, like vectors or hash maps, +as well as anything that requires function calls to be computed. + +# Syntax + +```ignore +lazy_static! { + [pub] static ref NAME_1: TYPE_1 = EXPR_1; + [pub] static ref NAME_2: TYPE_2 = EXPR_2; + ... + [pub] static ref NAME_N: TYPE_N = EXPR_N; +} +``` + +# Semantic + +For a given `static ref NAME: TYPE = EXPR;`, the macro generates a +unique type that implements `Deref<TYPE>` and stores it in a static with name `NAME`. + +On first deref, `EXPR` gets evaluated and stored internally, such that all further derefs +can return a reference to the same object. + +Like regular `static mut`s, this macro only works for types that fulfill the `Sync` +trait. + +# Example + +Using the macro: + +```rust +#[macro_use] +extern crate lazy_static; + +use std::collections::HashMap; + +lazy_static! { + static ref HASHMAP: HashMap<u32, &'static str> = { + let mut m = HashMap::new(); + m.insert(0, "foo"); + m.insert(1, "bar"); + m.insert(2, "baz"); + m + }; + static ref COUNT: usize = HASHMAP.len(); + static ref NUMBER: u32 = times_two(21); +} + +fn times_two(n: u32) -> u32 { n * 2 } + +fn main() { + println!("The map has {} entries.", *COUNT); + println!("The entry for `0` is \"{}\".", HASHMAP.get(&0).unwrap()); + println!("A expensive calculation on a static results in: {}.", *NUMBER); +} +``` + +# Implementation details + +The `Deref` implementation uses a hidden `static mut` that is guarded by a atomic check +using the `sync::Once` abstraction. All lazily evaluated values are currently +put in a heap allocated box, due to the Rust language currently not providing any way to +define uninitialized `static mut` values. + +*/</span> + +<span class='attribute'>#<span class='op'>!</span>[<span class='ident'>crate_type</span> <span class='op'>=</span> <span class='string'>"dylib"</span>]</span> + +<span class='attribute'>#[<span class='ident'>macro_export</span>]</span> +<span class='macro'>macro_rules</span><span class='macro'>!</span> <span class='ident'>lazy_static</span> { + (<span class='kw'>static</span> <span class='kw-2'>ref</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span>:<span class='ident'>ident</span> : <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span>:<span class='ident'>ty</span> <span class='op'>=</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>e</span>:<span class='ident'>expr</span>; $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>t</span>:<span class='ident'>tt</span>)<span class='op'>*</span>) <span class='op'>=></span> { + <span class='macro'>lazy_static</span><span class='macro'>!</span>(<span class='ident'>PRIV</span> <span class='kw'>static</span> <span class='kw-2'>ref</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span> : <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span> <span class='op'>=</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>e</span>; $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>t</span>)<span class='op'>*</span>); + }; + (<span class='kw'>pub</span> <span class='kw'>static</span> <span class='kw-2'>ref</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span>:<span class='ident'>ident</span> : <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span>:<span class='ident'>ty</span> <span class='op'>=</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>e</span>:<span class='ident'>expr</span>; $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>t</span>:<span class='ident'>tt</span>)<span class='op'>*</span>) <span class='op'>=></span> { + <span class='macro'>lazy_static</span><span class='macro'>!</span>(<span class='ident'>PUB</span> <span class='kw'>static</span> <span class='kw-2'>ref</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span> : <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span> <span class='op'>=</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>e</span>; $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>t</span>)<span class='op'>*</span>); + }; + (<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>VIS</span>:<span class='ident'>ident</span> <span class='kw'>static</span> <span class='kw-2'>ref</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span>:<span class='ident'>ident</span> : <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span>:<span class='ident'>ty</span> <span class='op'>=</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>e</span>:<span class='ident'>expr</span>; $(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>t</span>:<span class='ident'>tt</span>)<span class='op'>*</span>) <span class='op'>=></span> { + <span class='macro'>lazy_static</span><span class='macro'>!</span>(<span class='ident'>MAKE</span> <span class='ident'>TY</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>VIS</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span>); + <span class='kw'>impl</span> ::<span class='ident'>std</span>::<span class='ident'>ops</span>::<span class='ident'>Deref</span> <span class='kw'>for</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span> { + <span class='kw'>type</span> <span class='ident'>Target</span> <span class='op'>=</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span>; + <span class='kw'>fn</span> <span class='ident'>deref</span><span class='op'><</span><span class='lifetime'>'a</span><span class='op'>></span>(<span class='kw-2'>&</span><span class='lifetime'>'a</span> <span class='self'>self</span>) <span class='op'>-></span> <span class='kw-2'>&</span><span class='lifetime'>'a</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span> { + <span class='attribute'>#[<span class='ident'>inline</span>(<span class='ident'>always</span>)]</span> + <span class='kw'>fn</span> <span class='ident'>__static_ref_initialize</span>() <span class='op'>-></span> <span class='ident'>Box</span><span class='op'><</span><span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span><span class='op'>></span> { <span class='ident'>Box</span>::<span class='ident'>new</span>(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>e</span>) } + + <span class='kw'>unsafe</span> { + <span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>sync</span>::{<span class='ident'>Once</span>, <span class='ident'>ONCE_INIT</span>}; + <span class='kw'>use</span> <span class='ident'>std</span>::<span class='ident'>mem</span>::<span class='ident'>transmute</span>; + + <span class='attribute'>#[<span class='ident'>inline</span>(<span class='ident'>always</span>)]</span> + <span class='kw'>fn</span> <span class='ident'>require_sync</span><span class='op'><</span><span class='ident'>T</span>: <span class='ident'>Sync</span><span class='op'>></span>(_: <span class='kw-2'>&</span><span class='ident'>T</span>) { } + + <span class='kw'>static</span> <span class='kw-2'>mut</span> <span class='ident'>DATA</span>: <span class='op'>*</span><span class='kw'>const</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span> <span class='op'>=</span> <span class='number'>0</span> <span class='kw'>as</span> <span class='op'>*</span><span class='kw'>const</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span>; + <span class='kw'>static</span> <span class='kw-2'>mut</span> <span class='ident'>ONCE</span>: <span class='ident'>Once</span> <span class='op'>=</span> <span class='ident'>ONCE_INIT</span>; + <span class='ident'>ONCE</span>.<span class='ident'>call_once</span>(<span class='op'>||</span> { + <span class='ident'>DATA</span> <span class='op'>=</span> <span class='ident'>transmute</span>::<span class='op'><</span><span class='ident'>Box</span><span class='op'><</span><span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span><span class='op'>></span>, <span class='op'>*</span><span class='kw'>const</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>T</span><span class='op'>></span>(<span class='ident'>__static_ref_initialize</span>()); + }); + <span class='kw'>let</span> <span class='ident'>static_ref</span> <span class='op'>=</span> <span class='kw-2'>&</span><span class='op'>*</span><span class='ident'>DATA</span>; + <span class='ident'>require_sync</span>(<span class='ident'>static_ref</span>); + <span class='ident'>static_ref</span> + } + } + } + <span class='macro'>lazy_static</span><span class='macro'>!</span>($(<span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>t</span>)<span class='op'>*</span>); + }; + (<span class='ident'>MAKE</span> <span class='ident'>TY</span> <span class='ident'>PUB</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span>:<span class='ident'>ident</span>) <span class='op'>=></span> { + <span class='attribute'>#[<span class='ident'>allow</span>(<span class='ident'>missing_copy_implementations</span>)]</span> + <span class='attribute'>#[<span class='ident'>allow</span>(<span class='ident'>non_camel_case_types</span>)]</span> + <span class='attribute'>#[<span class='ident'>allow</span>(<span class='ident'>dead_code</span>)]</span> + <span class='kw'>pub</span> <span class='kw'>struct</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span> {<span class='ident'>__private_field</span>: ()} + <span class='kw'>pub</span> <span class='kw'>static</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span>: <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span> <span class='op'>=</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span> {<span class='ident'>__private_field</span>: ()}; + }; + (<span class='ident'>MAKE</span> <span class='ident'>TY</span> <span class='ident'>PRIV</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span>:<span class='ident'>ident</span>) <span class='op'>=></span> { + <span class='attribute'>#[<span class='ident'>allow</span>(<span class='ident'>missing_copy_implementations</span>)]</span> + <span class='attribute'>#[<span class='ident'>allow</span>(<span class='ident'>non_camel_case_types</span>)]</span> + <span class='attribute'>#[<span class='ident'>allow</span>(<span class='ident'>dead_code</span>)]</span> + <span class='kw'>struct</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span> {<span class='ident'>__private_field</span>: ()} + <span class='kw'>static</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span>: <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span> <span class='op'>=</span> <span class='macro-nonterminal'>$</span><span class='macro-nonterminal'>N</span> {<span class='ident'>__private_field</span>: ()}; + }; + () <span class='op'>=></span> () +} +</pre> +</section> + <section id='search' class="content hidden"></section> + + <section class="footer"></section> + + <div id="help" class="hidden"> + <div class="shortcuts"> + <h1>Keyboard shortcuts</h1> + <dl> + <dt>?</dt> + <dd>Show this help dialog</dd> + <dt>S</dt> + <dd>Focus the search field</dd> + <dt>⇤</dt> + <dd>Move up in search results</dd> + <dt>⇥</dt> + <dd>Move down in search results</dd> + <dt>⏎</dt> + <dd>Go to active search result</dd> + </dl> + </div> + <div class="infos"> + <h1>Search tricks</h1> + <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>typedef</code> (or + <code>tdef</code>). + </p> + <p> + Search functions by type signature (e.g. + <code>vec -> usize</code>) + </p> + </div> + </div> + + + + <script> + window.rootPath = "../../"; + window.currentCrate = "lazy_static"; + window.playgroundUrl = ""; + </script> + <script src="../../jquery.js"></script> + <script src="../../main.js"></script> + + <script async src="../../search-index.js"></script> +</body> +</html>
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