<!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 `src/libcollections/borrow.rs`.">
<meta name="keywords" content="rust, rustlang, rust-lang">
<title>borrow.rs.html -- source</title>
<link rel="stylesheet" type="text/css" href="../../normalize.css">
<link rel="stylesheet" type="text/css" href="../../rustdoc.css">
<link rel="stylesheet" type="text/css" href="../../main.css">
<link rel="shortcut icon" href="https://doc.rust-lang.org/favicon.ico">
</head>
<body class="rustdoc source">
<!--[if lte IE 8]>
<div class="warning">
This old browser is unsupported and will most likely display funky
things.
</div>
<![endif]-->
<nav class="sidebar">
<a href='../../collections/index.html'><img src='https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png' alt='logo' width='100'></a>
</nav>
<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"><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>
<span id="125">125</span>
<span id="126">126</span>
<span id="127">127</span>
<span id="128">128</span>
<span id="129">129</span>
<span id="130">130</span>
<span id="131">131</span>
<span id="132">132</span>
<span id="133">133</span>
<span id="134">134</span>
<span id="135">135</span>
<span id="136">136</span>
<span id="137">137</span>
<span id="138">138</span>
<span id="139">139</span>
<span id="140">140</span>
<span id="141">141</span>
<span id="142">142</span>
<span id="143">143</span>
<span id="144">144</span>
<span id="145">145</span>
<span id="146">146</span>
<span id="147">147</span>
<span id="148">148</span>
<span id="149">149</span>
<span id="150">150</span>
<span id="151">151</span>
<span id="152">152</span>
<span id="153">153</span>
<span id="154">154</span>
<span id="155">155</span>
<span id="156">156</span>
<span id="157">157</span>
<span id="158">158</span>
<span id="159">159</span>
<span id="160">160</span>
<span id="161">161</span>
<span id="162">162</span>
<span id="163">163</span>
<span id="164">164</span>
<span id="165">165</span>
<span id="166">166</span>
<span id="167">167</span>
<span id="168">168</span>
<span id="169">169</span>
<span id="170">170</span>
<span id="171">171</span>
<span id="172">172</span>
<span id="173">173</span>
<span id="174">174</span>
<span id="175">175</span>
<span id="176">176</span>
<span id="177">177</span>
<span id="178">178</span>
<span id="179">179</span>
<span id="180">180</span>
<span id="181">181</span>
<span id="182">182</span>
<span id="183">183</span>
<span id="184">184</span>
<span id="185">185</span>
<span id="186">186</span>
<span id="187">187</span>
<span id="188">188</span>
<span id="189">189</span>
<span id="190">190</span>
<span id="191">191</span>
<span id="192">192</span>
<span id="193">193</span>
<span id="194">194</span>
<span id="195">195</span>
<span id="196">196</span>
<span id="197">197</span>
<span id="198">198</span>
<span id="199">199</span>
<span id="200">200</span>
<span id="201">201</span>
<span id="202">202</span>
<span id="203">203</span>
<span id="204">204</span>
<span id="205">205</span>
<span id="206">206</span>
<span id="207">207</span>
<span id="208">208</span>
<span id="209">209</span>
<span id="210">210</span>
<span id="211">211</span>
<span id="212">212</span>
<span id="213">213</span>
<span id="214">214</span>
<span id="215">215</span>
<span id="216">216</span>
<span id="217">217</span>
<span id="218">218</span>
<span id="219">219</span>
<span id="220">220</span>
<span id="221">221</span>
<span id="222">222</span>
<span id="223">223</span>
<span id="224">224</span>
<span id="225">225</span>
<span id="226">226</span>
<span id="227">227</span>
<span id="228">228</span>
<span id="229">229</span>
<span id="230">230</span>
<span id="231">231</span>
<span id="232">232</span>
<span id="233">233</span>
<span id="234">234</span>
<span id="235">235</span>
<span id="236">236</span>
<span id="237">237</span>
<span id="238">238</span>
<span id="239">239</span>
<span id="240">240</span>
<span id="241">241</span>
<span id="242">242</span>
<span id="243">243</span>
<span id="244">244</span>
<span id="245">245</span>
<span id="246">246</span>
<span id="247">247</span>
<span id="248">248</span>
<span id="249">249</span>
<span id="250">250</span>
<span id="251">251</span>
<span id="252">252</span>
<span id="253">253</span>
<span id="254">254</span>
<span id="255">255</span>
<span id="256">256</span>
<span id="257">257</span>
<span id="258">258</span>
<span id="259">259</span>
<span id="260">260</span>
<span id="261">261</span>
<span id="262">262</span>
<span id="263">263</span>
<span id="264">264</span>
<span id="265">265</span>
<span id="266">266</span>
<span id="267">267</span>
<span id="268">268</span>
<span id="269">269</span>
<span id="270">270</span>
<span id="271">271</span>
<span id="272">272</span>
<span id="273">273</span>
<span id="274">274</span>
<span id="275">275</span>
<span id="276">276</span>
<span id="277">277</span>
<span id="278">278</span>
<span id="279">279</span>
<span id="280">280</span>
<span id="281">281</span>
<span id="282">282</span>
<span id="283">283</span>
<span id="284">284</span>
<span id="285">285</span>
<span id="286">286</span>
<span id="287">287</span>
<span id="288">288</span>
<span id="289">289</span>
<span id="290">290</span>
<span id="291">291</span>
<span id="292">292</span>
<span id="293">293</span>
<span id="294">294</span>
<span id="295">295</span>
<span id="296">296</span>
<span id="297">297</span>
<span id="298">298</span>
<span id="299">299</span>
<span id="300">300</span>
<span id="301">301</span>
<span id="302">302</span>
<span id="303">303</span>
<span id="304">304</span>
<span id="305">305</span>
<span id="306">306</span>
<span id="307">307</span>
<span id="308">308</span>
<span id="309">309</span>
<span id="310">310</span>
<span id="311">311</span>
<span id="312">312</span>
<span id="313">313</span>
<span id="314">314</span>
<span id="315">315</span>
<span id="316">316</span>
<span id="317">317</span>
<span id="318">318</span>
<span id="319">319</span>
<span id="320">320</span>
<span id="321">321</span>
<span id="322">322</span>
<span id="323">323</span>
<span id="324">324</span>
<span id="325">325</span>
<span id="326">326</span>
<span id="327">327</span>
<span id="328">328</span>
<span id="329">329</span>
<span id="330">330</span>
<span id="331">331</span>
<span id="332">332</span>
<span id="333">333</span>
<span id="334">334</span>
<span id="335">335</span>
<span id="336">336</span>
<span id="337">337</span>
<span id="338">338</span>
<span id="339">339</span>
<span id="340">340</span>
<span id="341">341</span>
<span id="342">342</span>
<span id="343">343</span>
<span id="344">344</span>
<span id="345">345</span>
<span id="346">346</span>
<span id="347">347</span>
<span id="348">348</span>
<span id="349">349</span>
<span id="350">350</span>
<span id="351">351</span>
<span id="352">352</span>
<span id="353">353</span>
<span id="354">354</span>
<span id="355">355</span>
<span id="356">356</span>
<span id="357">357</span>
<span id="358">358</span>
<span id="359">359</span>
<span id="360">360</span>
<span id="361">361</span>
<span id="362">362</span>
<span id="363">363</span>
<span id="364">364</span>
<span id="365">365</span>
<span id="366">366</span>
<span id="367">367</span>
<span id="368">368</span>
<span id="369">369</span>
<span id="370">370</span>
<span id="371">371</span>
<span id="372">372</span>
<span id="373">373</span>
<span id="374">374</span>
<span id="375">375</span>
<span id="376">376</span>
<span id="377">377</span>
<span id="378">378</span>
<span id="379">379</span>
<span id="380">380</span>
<span id="381">381</span>
<span id="382">382</span>
<span id="383">383</span>
<span id="384">384</span>
<span id="385">385</span>
<span id="386">386</span>
<span id="387">387</span>
<span id="388">388</span>
<span id="389">389</span>
<span id="390">390</span>
<span id="391">391</span>
<span id="392">392</span>
<span id="393">393</span>
<span id="394">394</span>
<span id="395">395</span>
<span id="396">396</span>
<span id="397">397</span>
<span id="398">398</span>
<span id="399">399</span>
<span id="400">400</span>
<span id="401">401</span>
<span id="402">402</span>
<span id="403">403</span>
<span id="404">404</span>
<span id="405">405</span>
<span id="406">406</span>
<span id="407">407</span>
<span id="408">408</span>
<span id="409">409</span>
<span id="410">410</span>
<span id="411">411</span>
<span id="412">412</span>
<span id="413">413</span>
<span id="414">414</span>
<span id="415">415</span>
<span id="416">416</span>
<span id="417">417</span>
<span id="418">418</span>
<span id="419">419</span>
<span id="420">420</span>
<span id="421">421</span>
</pre><pre class="rust ">
<span class="comment">// Copyright 2014 The Rust Project Developers. See the COPYRIGHT</span>
<span class="comment">// file at the top-level directory of this distribution and at</span>
<span class="comment">// http://rust-lang.org/COPYRIGHT.</span>
<span class="comment">//</span>
<span class="comment">// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or</span>
<span class="comment">// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license</span>
<span class="comment">// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your</span>
<span class="comment">// option. This file may not be copied, modified, or distributed</span>
<span class="comment">// except according to those terms.</span>
<span class="doccomment">//! A module for working with borrowed data.</span>
<span class="attribute">#<span class="op">!</span>[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">use</span> <span class="ident">core</span>::<span class="ident">cmp</span>::<span class="ident">Ordering</span>;
<span class="kw">use</span> <span class="ident">core</span>::<span class="ident">hash</span>::{<span class="ident">Hash</span>, <span class="ident">Hasher</span>};
<span class="kw">use</span> <span class="ident">core</span>::<span class="ident">ops</span>::{<span class="ident">Add</span>, <span class="ident">AddAssign</span>, <span class="ident">Deref</span>};
<span class="kw">use</span> <span class="ident">fmt</span>;
<span class="kw">use</span> <span class="ident">string</span>::<span class="ident">String</span>;
<span class="kw">use</span> <span class="self">self</span>::<span class="ident">Cow</span>::<span class="kw-2">*</span>;
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">core</span>::<span class="ident">borrow</span>::{<span class="ident">Borrow</span>, <span class="ident">BorrowMut</span>};
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">Borrow</span><span class="op"><</span><span class="ident">B</span><span class="op">></span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">ToOwned</span>,
<span class="op"><</span><span class="ident">B</span> <span class="kw">as</span> <span class="ident">ToOwned</span><span class="op">></span>::<span class="ident">Owned</span>: <span class="lifetime">'a</span>
{
<span class="kw">fn</span> <span class="ident">borrow</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="kw-2">&</span><span class="ident">B</span> {
<span class="kw-2">&</span><span class="kw-2">*</span><span class="kw-2">*</span><span class="self">self</span>
}
}
<span class="doccomment">/// A generalization of `Clone` to borrowed data.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Some types make it possible to go from borrowed to owned, usually by</span>
<span class="doccomment">/// implementing the `Clone` trait. But `Clone` works only for going from `&T`</span>
<span class="doccomment">/// to `T`. The `ToOwned` trait generalizes `Clone` to construct owned data</span>
<span class="doccomment">/// from any borrow of a given type.</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">pub</span> <span class="kw">trait</span> <span class="ident">ToOwned</span> {
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">type</span> <span class="ident">Owned</span>: <span class="ident">Borrow</span><span class="op"><</span><span class="self">Self</span><span class="op">></span>;
<span class="doccomment">/// Creates owned data from borrowed data, usually by cloning.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Basic usage:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let s: &str = "a";</span>
<span class="doccomment">/// let ss: String = s.to_owned();</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let v: &[i32] = &[1, 2];</span>
<span class="doccomment">/// let vv: Vec<i32> = v.to_owned();</span>
<span class="doccomment">/// ```</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">fn</span> <span class="ident">to_owned</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="self">Self</span>::<span class="ident">Owned</span>;
<span class="doccomment">/// Uses borrowed data to replace owned data, usually by cloning.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This is borrow-generalized version of `Clone::clone_from`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Basic usage:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// # #![feature(toowned_clone_into)]</span>
<span class="doccomment">/// let mut s: String = String::new();</span>
<span class="doccomment">/// "hello".clone_into(&mut s);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let mut v: Vec<i32> = Vec::new();</span>
<span class="doccomment">/// [1, 2][..].clone_into(&mut v);</span>
<span class="doccomment">/// ```</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"toowned_clone_into"</span>,
<span class="ident">reason</span> <span class="op">=</span> <span class="string">"recently added"</span>,
<span class="ident">issue</span> <span class="op">=</span> <span class="string">"41263"</span>)]</span>
<span class="kw">fn</span> <span class="ident">clone_into</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">target</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">Self</span>::<span class="ident">Owned</span>) {
<span class="kw-2">*</span><span class="ident">target</span> <span class="op">=</span> <span class="self">self</span>.<span class="ident">to_owned</span>();
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> <span class="ident">ToOwned</span> <span class="kw">for</span> <span class="ident">T</span>
<span class="kw">where</span> <span class="ident">T</span>: <span class="ident">Clone</span>
{
<span class="kw">type</span> <span class="ident">Owned</span> <span class="op">=</span> <span class="ident">T</span>;
<span class="kw">fn</span> <span class="ident">to_owned</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="ident">T</span> {
<span class="self">self</span>.<span class="ident">clone</span>()
}
<span class="kw">fn</span> <span class="ident">clone_into</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">target</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">T</span>) {
<span class="ident">target</span>.<span class="ident">clone_from</span>(<span class="self">self</span>);
}
}
<span class="doccomment">/// A clone-on-write smart pointer.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The type `Cow` is a smart pointer providing clone-on-write functionality: it</span>
<span class="doccomment">/// can enclose and provide immutable access to borrowed data, and clone the</span>
<span class="doccomment">/// data lazily when mutation or ownership is required. The type is designed to</span>
<span class="doccomment">/// work with general borrowed data via the `Borrow` trait.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// `Cow` implements `Deref`, which means that you can call</span>
<span class="doccomment">/// non-mutating methods directly on the data it encloses. If mutation</span>
<span class="doccomment">/// is desired, `to_mut` will obtain a mutable reference to an owned</span>
<span class="doccomment">/// value, cloning if necessary.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// use std::borrow::Cow;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// fn abs_all(input: &mut Cow<[i32]>) {</span>
<span class="doccomment">/// for i in 0..input.len() {</span>
<span class="doccomment">/// let v = input[i];</span>
<span class="doccomment">/// if v < 0 {</span>
<span class="doccomment">/// // Clones into a vector if not already owned.</span>
<span class="doccomment">/// input.to_mut()[i] = -v;</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// }</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // No clone occurs because `input` doesn't need to be mutated.</span>
<span class="doccomment">/// let slice = [0, 1, 2];</span>
<span class="doccomment">/// let mut input = Cow::from(&slice[..]);</span>
<span class="doccomment">/// abs_all(&mut input);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // Clone occurs because `input` needs to be mutated.</span>
<span class="doccomment">/// let slice = [-1, 0, 1];</span>
<span class="doccomment">/// let mut input = Cow::from(&slice[..]);</span>
<span class="doccomment">/// abs_all(&mut input);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // No clone occurs because `input` is already owned.</span>
<span class="doccomment">/// let mut input = Cow::from(vec![-1, 0, 1]);</span>
<span class="doccomment">/// abs_all(&mut input);</span>
<span class="doccomment">/// ```</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">pub</span> <span class="kw">enum</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span> <span class="op">+</span> <span class="lifetime">'a</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">ToOwned</span>
{
<span class="doccomment">/// Borrowed data.</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="ident">Borrowed</span>(<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw-2">&</span><span class="lifetime">'a</span> <span class="ident">B</span>),
<span class="doccomment">/// Owned data.</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="ident">Owned</span>(<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="op"><</span><span class="ident">B</span> <span class="kw">as</span> <span class="ident">ToOwned</span><span class="op">></span>::<span class="ident">Owned</span>),
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">Clone</span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">ToOwned</span>
{
<span class="kw">fn</span> <span class="ident">clone</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span> {
<span class="kw">match</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="ident">Borrowed</span>(<span class="ident">b</span>) <span class="op">=></span> <span class="ident">Borrowed</span>(<span class="ident">b</span>),
<span class="ident">Owned</span>(<span class="kw-2">ref</span> <span class="ident">o</span>) <span class="op">=></span> {
<span class="kw">let</span> <span class="ident">b</span>: <span class="kw-2">&</span><span class="ident">B</span> <span class="op">=</span> <span class="ident">o</span>.<span class="ident">borrow</span>();
<span class="ident">Owned</span>(<span class="ident">b</span>.<span class="ident">to_owned</span>())
}
}
}
<span class="kw">fn</span> <span class="ident">clone_from</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">source</span>: <span class="kw-2">&</span><span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>) {
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Owned</span>(<span class="kw-2">ref</span> <span class="kw-2">mut</span> <span class="ident">dest</span>) <span class="op">=</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Owned</span>(<span class="kw-2">ref</span> <span class="ident">o</span>) <span class="op">=</span> <span class="kw-2">*</span><span class="ident">source</span> {
<span class="ident">o</span>.<span class="ident">borrow</span>().<span class="ident">clone_into</span>(<span class="ident">dest</span>);
<span class="kw">return</span>;
}
}
<span class="kw-2">*</span><span class="self">self</span> <span class="op">=</span> <span class="ident">source</span>.<span class="ident">clone</span>();
}
}
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">ToOwned</span>
{
<span class="doccomment">/// Acquires a mutable reference to the owned form of the data.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Clones the data if it is not already owned.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// use std::ascii::AsciiExt;</span>
<span class="doccomment">/// use std::borrow::Cow;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let mut cow = Cow::Borrowed("foo");</span>
<span class="doccomment">/// cow.to_mut().make_ascii_uppercase();</span>
<span class="doccomment">///</span>
<span class="doccomment">/// assert_eq!(</span>
<span class="doccomment">/// cow,</span>
<span class="doccomment">/// Cow::Owned(String::from("FOO")) as Cow<str></span>
<span class="doccomment">/// );</span>
<span class="doccomment">/// ```</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">to_mut</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>) <span class="op">-></span> <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="op"><</span><span class="ident">B</span> <span class="kw">as</span> <span class="ident">ToOwned</span><span class="op">></span>::<span class="ident">Owned</span> {
<span class="kw">match</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="ident">Borrowed</span>(<span class="ident">borrowed</span>) <span class="op">=></span> {
<span class="kw-2">*</span><span class="self">self</span> <span class="op">=</span> <span class="ident">Owned</span>(<span class="ident">borrowed</span>.<span class="ident">to_owned</span>());
<span class="kw">match</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="ident">Borrowed</span>(..) <span class="op">=></span> <span class="macro">unreachable</span><span class="macro">!</span>(),
<span class="ident">Owned</span>(<span class="kw-2">ref</span> <span class="kw-2">mut</span> <span class="ident">owned</span>) <span class="op">=></span> <span class="ident">owned</span>,
}
}
<span class="ident">Owned</span>(<span class="kw-2">ref</span> <span class="kw-2">mut</span> <span class="ident">owned</span>) <span class="op">=></span> <span class="ident">owned</span>,
}
}
<span class="doccomment">/// Extracts the owned data.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Clones the data if it is not already owned.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Calling `into_owned` on a `Cow::Borrowed` clones the underlying data</span>
<span class="doccomment">/// and becomes a `Cow::Owned`:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// use std::borrow::Cow;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let s = "Hello world!";</span>
<span class="doccomment">/// let cow = Cow::Borrowed(s);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// assert_eq!(</span>
<span class="doccomment">/// cow.into_owned(),</span>
<span class="doccomment">/// Cow::Owned(String::from(s))</span>
<span class="doccomment">/// );</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Calling `into_owned` on a `Cow::Owned` is a no-op:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// use std::borrow::Cow;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let s = "Hello world!";</span>
<span class="doccomment">/// let cow: Cow<str> = Cow::Owned(String::from(s));</span>
<span class="doccomment">///</span>
<span class="doccomment">/// assert_eq!(</span>
<span class="doccomment">/// cow.into_owned(),</span>
<span class="doccomment">/// Cow::Owned(String::from(s))</span>
<span class="doccomment">/// );</span>
<span class="doccomment">/// ```</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">into_owned</span>(<span class="self">self</span>) <span class="op">-></span> <span class="op"><</span><span class="ident">B</span> <span class="kw">as</span> <span class="ident">ToOwned</span><span class="op">></span>::<span class="ident">Owned</span> {
<span class="kw">match</span> <span class="self">self</span> {
<span class="ident">Borrowed</span>(<span class="ident">borrowed</span>) <span class="op">=></span> <span class="ident">borrowed</span>.<span class="ident">to_owned</span>(),
<span class="ident">Owned</span>(<span class="ident">owned</span>) <span class="op">=></span> <span class="ident">owned</span>,
}
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">Deref</span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">ToOwned</span>
{
<span class="kw">type</span> <span class="ident">Target</span> <span class="op">=</span> <span class="ident">B</span>;
<span class="kw">fn</span> <span class="ident">deref</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="kw-2">&</span><span class="ident">B</span> {
<span class="kw">match</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="ident">Borrowed</span>(<span class="ident">borrowed</span>) <span class="op">=></span> <span class="ident">borrowed</span>,
<span class="ident">Owned</span>(<span class="kw-2">ref</span> <span class="ident">owned</span>) <span class="op">=></span> <span class="ident">owned</span>.<span class="ident">borrow</span>(),
}
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">Eq</span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span> <span class="kw">where</span> <span class="ident">B</span>: <span class="ident">Eq</span> <span class="op">+</span> <span class="ident">ToOwned</span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">Ord</span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">Ord</span> <span class="op">+</span> <span class="ident">ToOwned</span>
{
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">cmp</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">other</span>: <span class="kw-2">&</span><span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>) <span class="op">-></span> <span class="ident">Ordering</span> {
<span class="ident">Ord</span>::<span class="ident">cmp</span>(<span class="kw-2">&</span><span class="kw-2">*</span><span class="kw-2">*</span><span class="self">self</span>, <span class="kw-2">&</span><span class="kw-2">*</span><span class="kw-2">*</span><span class="ident">other</span>)
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="lifetime">'b</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span>, <span class="ident">C</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">PartialEq</span><span class="op"><</span><span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'b</span>, <span class="ident">C</span><span class="op">>></span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">PartialEq</span><span class="op"><</span><span class="ident">C</span><span class="op">></span> <span class="op">+</span> <span class="ident">ToOwned</span>,
<span class="ident">C</span>: <span class="ident">ToOwned</span>
{
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">eq</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">other</span>: <span class="kw-2">&</span><span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'b</span>, <span class="ident">C</span><span class="op">></span>) <span class="op">-></span> <span class="ident">bool</span> {
<span class="ident">PartialEq</span>::<span class="ident">eq</span>(<span class="kw-2">&</span><span class="kw-2">*</span><span class="kw-2">*</span><span class="self">self</span>, <span class="kw-2">&</span><span class="kw-2">*</span><span class="kw-2">*</span><span class="ident">other</span>)
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">PartialOrd</span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">PartialOrd</span> <span class="op">+</span> <span class="ident">ToOwned</span>
{
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">partial_cmp</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">other</span>: <span class="kw-2">&</span><span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>) <span class="op">-></span> <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">Ordering</span><span class="op">></span> {
<span class="ident">PartialOrd</span>::<span class="ident">partial_cmp</span>(<span class="kw-2">&</span><span class="kw-2">*</span><span class="kw-2">*</span><span class="self">self</span>, <span class="kw-2">&</span><span class="kw-2">*</span><span class="kw-2">*</span><span class="ident">other</span>)
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">fmt</span>::<span class="ident">Debug</span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">fmt</span>::<span class="ident">Debug</span> <span class="op">+</span> <span class="ident">ToOwned</span>,
<span class="op"><</span><span class="ident">B</span> <span class="kw">as</span> <span class="ident">ToOwned</span><span class="op">></span>::<span class="ident">Owned</span>: <span class="ident">fmt</span>::<span class="ident">Debug</span>
{
<span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">f</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-></span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> {
<span class="kw">match</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="ident">Borrowed</span>(<span class="kw-2">ref</span> <span class="ident">b</span>) <span class="op">=></span> <span class="ident">fmt</span>::<span class="ident">Debug</span>::<span class="ident">fmt</span>(<span class="ident">b</span>, <span class="ident">f</span>),
<span class="ident">Owned</span>(<span class="kw-2">ref</span> <span class="ident">o</span>) <span class="op">=></span> <span class="ident">fmt</span>::<span class="ident">Debug</span>::<span class="ident">fmt</span>(<span class="ident">o</span>, <span class="ident">f</span>),
}
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">fmt</span>::<span class="ident">Display</span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">fmt</span>::<span class="ident">Display</span> <span class="op">+</span> <span class="ident">ToOwned</span>,
<span class="op"><</span><span class="ident">B</span> <span class="kw">as</span> <span class="ident">ToOwned</span><span class="op">></span>::<span class="ident">Owned</span>: <span class="ident">fmt</span>::<span class="ident">Display</span>
{
<span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">f</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-></span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> {
<span class="kw">match</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="ident">Borrowed</span>(<span class="kw-2">ref</span> <span class="ident">b</span>) <span class="op">=></span> <span class="ident">fmt</span>::<span class="ident">Display</span>::<span class="ident">fmt</span>(<span class="ident">b</span>, <span class="ident">f</span>),
<span class="ident">Owned</span>(<span class="kw-2">ref</span> <span class="ident">o</span>) <span class="op">=></span> <span class="ident">fmt</span>::<span class="ident">Display</span>::<span class="ident">fmt</span>(<span class="ident">o</span>, <span class="ident">f</span>),
}
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"default"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.11.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">Default</span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">ToOwned</span>,
<span class="op"><</span><span class="ident">B</span> <span class="kw">as</span> <span class="ident">ToOwned</span><span class="op">></span>::<span class="ident">Owned</span>: <span class="ident">Default</span>
{
<span class="doccomment">/// Creates an owned Cow<'a, B> with the default value for the contained owned value.</span>
<span class="kw">fn</span> <span class="ident">default</span>() <span class="op">-></span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span> {
<span class="ident">Owned</span>(<span class="op"><</span><span class="ident">B</span> <span class="kw">as</span> <span class="ident">ToOwned</span><span class="op">></span>::<span class="ident">Owned</span>::<span class="ident">default</span>())
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">Hash</span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">B</span><span class="op">></span>
<span class="kw">where</span> <span class="ident">B</span>: <span class="ident">Hash</span> <span class="op">+</span> <span class="ident">ToOwned</span>
{
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">hash</span><span class="op"><</span><span class="ident">H</span>: <span class="ident">Hasher</span><span class="op">></span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">state</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">H</span>) {
<span class="ident">Hash</span>::<span class="ident">hash</span>(<span class="kw-2">&</span><span class="kw-2">*</span><span class="kw-2">*</span><span class="self">self</span>, <span class="ident">state</span>)
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"rust1"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.0.0"</span>)]</span>
<span class="attribute">#[<span class="ident">allow</span>(<span class="ident">deprecated</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">T</span>: <span class="question-mark">?</span><span class="ident">Sized</span> <span class="op">+</span> <span class="ident">ToOwned</span><span class="op">></span> <span class="ident">AsRef</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">T</span><span class="op">></span> {
<span class="kw">fn</span> <span class="ident">as_ref</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="kw-2">&</span><span class="ident">T</span> {
<span class="self">self</span>
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"cow_add"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.14.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span><span class="op">></span> <span class="ident">Add</span><span class="op"><</span><span class="kw-2">&</span><span class="lifetime">'a</span> <span class="ident">str</span><span class="op">></span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">str</span><span class="op">></span> {
<span class="kw">type</span> <span class="ident">Output</span> <span class="op">=</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">str</span><span class="op">></span>;
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">add</span>(<span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">rhs</span>: <span class="kw-2">&</span><span class="lifetime">'a</span> <span class="ident">str</span>) <span class="op">-></span> <span class="self">Self</span>::<span class="ident">Output</span> {
<span class="self">self</span> <span class="op">+=</span> <span class="ident">rhs</span>;
<span class="self">self</span>
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"cow_add"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.14.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span><span class="op">></span> <span class="ident">Add</span><span class="op"><</span><span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">str</span><span class="op">>></span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">str</span><span class="op">></span> {
<span class="kw">type</span> <span class="ident">Output</span> <span class="op">=</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">str</span><span class="op">></span>;
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">add</span>(<span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">rhs</span>: <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">str</span><span class="op">></span>) <span class="op">-></span> <span class="self">Self</span>::<span class="ident">Output</span> {
<span class="self">self</span> <span class="op">+=</span> <span class="ident">rhs</span>;
<span class="self">self</span>
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"cow_add"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.14.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span><span class="op">></span> <span class="ident">AddAssign</span><span class="op"><</span><span class="kw-2">&</span><span class="lifetime">'a</span> <span class="ident">str</span><span class="op">></span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">str</span><span class="op">></span> {
<span class="kw">fn</span> <span class="ident">add_assign</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">rhs</span>: <span class="kw-2">&</span><span class="lifetime">'a</span> <span class="ident">str</span>) {
<span class="kw">if</span> <span class="self">self</span>.<span class="ident">is_empty</span>() {
<span class="kw-2">*</span><span class="self">self</span> <span class="op">=</span> <span class="ident">Cow</span>::<span class="ident">Borrowed</span>(<span class="ident">rhs</span>)
} <span class="kw">else</span> <span class="kw">if</span> <span class="ident">rhs</span>.<span class="ident">is_empty</span>() {
<span class="kw">return</span>;
} <span class="kw">else</span> {
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Cow</span>::<span class="ident">Borrowed</span>(<span class="ident">lhs</span>) <span class="op">=</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">with_capacity</span>(<span class="ident">lhs</span>.<span class="ident">len</span>() <span class="op">+</span> <span class="ident">rhs</span>.<span class="ident">len</span>());
<span class="ident">s</span>.<span class="ident">push_str</span>(<span class="ident">lhs</span>);
<span class="kw-2">*</span><span class="self">self</span> <span class="op">=</span> <span class="ident">Cow</span>::<span class="ident">Owned</span>(<span class="ident">s</span>);
}
<span class="self">self</span>.<span class="ident">to_mut</span>().<span class="ident">push_str</span>(<span class="ident">rhs</span>);
}
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"cow_add"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.14.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="lifetime">'a</span><span class="op">></span> <span class="ident">AddAssign</span><span class="op"><</span><span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">str</span><span class="op">>></span> <span class="kw">for</span> <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">str</span><span class="op">></span> {
<span class="kw">fn</span> <span class="ident">add_assign</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">rhs</span>: <span class="ident">Cow</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">str</span><span class="op">></span>) {
<span class="kw">if</span> <span class="self">self</span>.<span class="ident">is_empty</span>() {
<span class="kw-2">*</span><span class="self">self</span> <span class="op">=</span> <span class="ident">rhs</span>
} <span class="kw">else</span> <span class="kw">if</span> <span class="ident">rhs</span>.<span class="ident">is_empty</span>() {
<span class="kw">return</span>;
} <span class="kw">else</span> {
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Cow</span>::<span class="ident">Borrowed</span>(<span class="ident">lhs</span>) <span class="op">=</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">with_capacity</span>(<span class="ident">lhs</span>.<span class="ident">len</span>() <span class="op">+</span> <span class="ident">rhs</span>.<span class="ident">len</span>());
<span class="ident">s</span>.<span class="ident">push_str</span>(<span class="ident">lhs</span>);
<span class="kw-2">*</span><span class="self">self</span> <span class="op">=</span> <span class="ident">Cow</span>::<span class="ident">Owned</span>(<span class="ident">s</span>);
}
<span class="self">self</span>.<span class="ident">to_mut</span>().<span class="ident">push_str</span>(<span class="kw-2">&</span><span class="ident">rhs</span>);
}
}
}
</pre>
</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>?</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>
<dt>+</dt>
<dd>Collapse/expand 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 = "collections";
</script>
<script src="../../main.js"></script>
<script defer src="../../search-index.js"></script>
</body>
</html>
distrib
>
Mageia
>
6
>
armv7hl
>
media
>
core-updates
>
by-pkgid
>
564935689ab5527f955e5449ded02799
>
files
>
2592
