Sophie

Sophie

distrib > Mageia > 6 > armv7hl > media > core-updates > by-pkgid > 4e2dbb669434a7691662cb2f0ad38972 > files > 11806

rust-doc-1.28.0-1.mga6.armv7hl.rpm

<!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 `libstd/primitive_docs.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>primitive_docs.rs.html -- source</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><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"><div class="sidebar-menu">&#9776;</div><a href='../../std/index.html'><img src='https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png' alt='logo' width='100'></a></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"><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>
<span id="422"> 422</span>
<span id="423"> 423</span>
<span id="424"> 424</span>
<span id="425"> 425</span>
<span id="426"> 426</span>
<span id="427"> 427</span>
<span id="428"> 428</span>
<span id="429"> 429</span>
<span id="430"> 430</span>
<span id="431"> 431</span>
<span id="432"> 432</span>
<span id="433"> 433</span>
<span id="434"> 434</span>
<span id="435"> 435</span>
<span id="436"> 436</span>
<span id="437"> 437</span>
<span id="438"> 438</span>
<span id="439"> 439</span>
<span id="440"> 440</span>
<span id="441"> 441</span>
<span id="442"> 442</span>
<span id="443"> 443</span>
<span id="444"> 444</span>
<span id="445"> 445</span>
<span id="446"> 446</span>
<span id="447"> 447</span>
<span id="448"> 448</span>
<span id="449"> 449</span>
<span id="450"> 450</span>
<span id="451"> 451</span>
<span id="452"> 452</span>
<span id="453"> 453</span>
<span id="454"> 454</span>
<span id="455"> 455</span>
<span id="456"> 456</span>
<span id="457"> 457</span>
<span id="458"> 458</span>
<span id="459"> 459</span>
<span id="460"> 460</span>
<span id="461"> 461</span>
<span id="462"> 462</span>
<span id="463"> 463</span>
<span id="464"> 464</span>
<span id="465"> 465</span>
<span id="466"> 466</span>
<span id="467"> 467</span>
<span id="468"> 468</span>
<span id="469"> 469</span>
<span id="470"> 470</span>
<span id="471"> 471</span>
<span id="472"> 472</span>
<span id="473"> 473</span>
<span id="474"> 474</span>
<span id="475"> 475</span>
<span id="476"> 476</span>
<span id="477"> 477</span>
<span id="478"> 478</span>
<span id="479"> 479</span>
<span id="480"> 480</span>
<span id="481"> 481</span>
<span id="482"> 482</span>
<span id="483"> 483</span>
<span id="484"> 484</span>
<span id="485"> 485</span>
<span id="486"> 486</span>
<span id="487"> 487</span>
<span id="488"> 488</span>
<span id="489"> 489</span>
<span id="490"> 490</span>
<span id="491"> 491</span>
<span id="492"> 492</span>
<span id="493"> 493</span>
<span id="494"> 494</span>
<span id="495"> 495</span>
<span id="496"> 496</span>
<span id="497"> 497</span>
<span id="498"> 498</span>
<span id="499"> 499</span>
<span id="500"> 500</span>
<span id="501"> 501</span>
<span id="502"> 502</span>
<span id="503"> 503</span>
<span id="504"> 504</span>
<span id="505"> 505</span>
<span id="506"> 506</span>
<span id="507"> 507</span>
<span id="508"> 508</span>
<span id="509"> 509</span>
<span id="510"> 510</span>
<span id="511"> 511</span>
<span id="512"> 512</span>
<span id="513"> 513</span>
<span id="514"> 514</span>
<span id="515"> 515</span>
<span id="516"> 516</span>
<span id="517"> 517</span>
<span id="518"> 518</span>
<span id="519"> 519</span>
<span id="520"> 520</span>
<span id="521"> 521</span>
<span id="522"> 522</span>
<span id="523"> 523</span>
<span id="524"> 524</span>
<span id="525"> 525</span>
<span id="526"> 526</span>
<span id="527"> 527</span>
<span id="528"> 528</span>
<span id="529"> 529</span>
<span id="530"> 530</span>
<span id="531"> 531</span>
<span id="532"> 532</span>
<span id="533"> 533</span>
<span id="534"> 534</span>
<span id="535"> 535</span>
<span id="536"> 536</span>
<span id="537"> 537</span>
<span id="538"> 538</span>
<span id="539"> 539</span>
<span id="540"> 540</span>
<span id="541"> 541</span>
<span id="542"> 542</span>
<span id="543"> 543</span>
<span id="544"> 544</span>
<span id="545"> 545</span>
<span id="546"> 546</span>
<span id="547"> 547</span>
<span id="548"> 548</span>
<span id="549"> 549</span>
<span id="550"> 550</span>
<span id="551"> 551</span>
<span id="552"> 552</span>
<span id="553"> 553</span>
<span id="554"> 554</span>
<span id="555"> 555</span>
<span id="556"> 556</span>
<span id="557"> 557</span>
<span id="558"> 558</span>
<span id="559"> 559</span>
<span id="560"> 560</span>
<span id="561"> 561</span>
<span id="562"> 562</span>
<span id="563"> 563</span>
<span id="564"> 564</span>
<span id="565"> 565</span>
<span id="566"> 566</span>
<span id="567"> 567</span>
<span id="568"> 568</span>
<span id="569"> 569</span>
<span id="570"> 570</span>
<span id="571"> 571</span>
<span id="572"> 572</span>
<span id="573"> 573</span>
<span id="574"> 574</span>
<span id="575"> 575</span>
<span id="576"> 576</span>
<span id="577"> 577</span>
<span id="578"> 578</span>
<span id="579"> 579</span>
<span id="580"> 580</span>
<span id="581"> 581</span>
<span id="582"> 582</span>
<span id="583"> 583</span>
<span id="584"> 584</span>
<span id="585"> 585</span>
<span id="586"> 586</span>
<span id="587"> 587</span>
<span id="588"> 588</span>
<span id="589"> 589</span>
<span id="590"> 590</span>
<span id="591"> 591</span>
<span id="592"> 592</span>
<span id="593"> 593</span>
<span id="594"> 594</span>
<span id="595"> 595</span>
<span id="596"> 596</span>
<span id="597"> 597</span>
<span id="598"> 598</span>
<span id="599"> 599</span>
<span id="600"> 600</span>
<span id="601"> 601</span>
<span id="602"> 602</span>
<span id="603"> 603</span>
<span id="604"> 604</span>
<span id="605"> 605</span>
<span id="606"> 606</span>
<span id="607"> 607</span>
<span id="608"> 608</span>
<span id="609"> 609</span>
<span id="610"> 610</span>
<span id="611"> 611</span>
<span id="612"> 612</span>
<span id="613"> 613</span>
<span id="614"> 614</span>
<span id="615"> 615</span>
<span id="616"> 616</span>
<span id="617"> 617</span>
<span id="618"> 618</span>
<span id="619"> 619</span>
<span id="620"> 620</span>
<span id="621"> 621</span>
<span id="622"> 622</span>
<span id="623"> 623</span>
<span id="624"> 624</span>
<span id="625"> 625</span>
<span id="626"> 626</span>
<span id="627"> 627</span>
<span id="628"> 628</span>
<span id="629"> 629</span>
<span id="630"> 630</span>
<span id="631"> 631</span>
<span id="632"> 632</span>
<span id="633"> 633</span>
<span id="634"> 634</span>
<span id="635"> 635</span>
<span id="636"> 636</span>
<span id="637"> 637</span>
<span id="638"> 638</span>
<span id="639"> 639</span>
<span id="640"> 640</span>
<span id="641"> 641</span>
<span id="642"> 642</span>
<span id="643"> 643</span>
<span id="644"> 644</span>
<span id="645"> 645</span>
<span id="646"> 646</span>
<span id="647"> 647</span>
<span id="648"> 648</span>
<span id="649"> 649</span>
<span id="650"> 650</span>
<span id="651"> 651</span>
<span id="652"> 652</span>
<span id="653"> 653</span>
<span id="654"> 654</span>
<span id="655"> 655</span>
<span id="656"> 656</span>
<span id="657"> 657</span>
<span id="658"> 658</span>
<span id="659"> 659</span>
<span id="660"> 660</span>
<span id="661"> 661</span>
<span id="662"> 662</span>
<span id="663"> 663</span>
<span id="664"> 664</span>
<span id="665"> 665</span>
<span id="666"> 666</span>
<span id="667"> 667</span>
<span id="668"> 668</span>
<span id="669"> 669</span>
<span id="670"> 670</span>
<span id="671"> 671</span>
<span id="672"> 672</span>
<span id="673"> 673</span>
<span id="674"> 674</span>
<span id="675"> 675</span>
<span id="676"> 676</span>
<span id="677"> 677</span>
<span id="678"> 678</span>
<span id="679"> 679</span>
<span id="680"> 680</span>
<span id="681"> 681</span>
<span id="682"> 682</span>
<span id="683"> 683</span>
<span id="684"> 684</span>
<span id="685"> 685</span>
<span id="686"> 686</span>
<span id="687"> 687</span>
<span id="688"> 688</span>
<span id="689"> 689</span>
<span id="690"> 690</span>
<span id="691"> 691</span>
<span id="692"> 692</span>
<span id="693"> 693</span>
<span id="694"> 694</span>
<span id="695"> 695</span>
<span id="696"> 696</span>
<span id="697"> 697</span>
<span id="698"> 698</span>
<span id="699"> 699</span>
<span id="700"> 700</span>
<span id="701"> 701</span>
<span id="702"> 702</span>
<span id="703"> 703</span>
<span id="704"> 704</span>
<span id="705"> 705</span>
<span id="706"> 706</span>
<span id="707"> 707</span>
<span id="708"> 708</span>
<span id="709"> 709</span>
<span id="710"> 710</span>
<span id="711"> 711</span>
<span id="712"> 712</span>
<span id="713"> 713</span>
<span id="714"> 714</span>
<span id="715"> 715</span>
<span id="716"> 716</span>
<span id="717"> 717</span>
<span id="718"> 718</span>
<span id="719"> 719</span>
<span id="720"> 720</span>
<span id="721"> 721</span>
<span id="722"> 722</span>
<span id="723"> 723</span>
<span id="724"> 724</span>
<span id="725"> 725</span>
<span id="726"> 726</span>
<span id="727"> 727</span>
<span id="728"> 728</span>
<span id="729"> 729</span>
<span id="730"> 730</span>
<span id="731"> 731</span>
<span id="732"> 732</span>
<span id="733"> 733</span>
<span id="734"> 734</span>
<span id="735"> 735</span>
<span id="736"> 736</span>
<span id="737"> 737</span>
<span id="738"> 738</span>
<span id="739"> 739</span>
<span id="740"> 740</span>
<span id="741"> 741</span>
<span id="742"> 742</span>
<span id="743"> 743</span>
<span id="744"> 744</span>
<span id="745"> 745</span>
<span id="746"> 746</span>
<span id="747"> 747</span>
<span id="748"> 748</span>
<span id="749"> 749</span>
<span id="750"> 750</span>
<span id="751"> 751</span>
<span id="752"> 752</span>
<span id="753"> 753</span>
<span id="754"> 754</span>
<span id="755"> 755</span>
<span id="756"> 756</span>
<span id="757"> 757</span>
<span id="758"> 758</span>
<span id="759"> 759</span>
<span id="760"> 760</span>
<span id="761"> 761</span>
<span id="762"> 762</span>
<span id="763"> 763</span>
<span id="764"> 764</span>
<span id="765"> 765</span>
<span id="766"> 766</span>
<span id="767"> 767</span>
<span id="768"> 768</span>
<span id="769"> 769</span>
<span id="770"> 770</span>
<span id="771"> 771</span>
<span id="772"> 772</span>
<span id="773"> 773</span>
<span id="774"> 774</span>
<span id="775"> 775</span>
<span id="776"> 776</span>
<span id="777"> 777</span>
<span id="778"> 778</span>
<span id="779"> 779</span>
<span id="780"> 780</span>
<span id="781"> 781</span>
<span id="782"> 782</span>
<span id="783"> 783</span>
<span id="784"> 784</span>
<span id="785"> 785</span>
<span id="786"> 786</span>
<span id="787"> 787</span>
<span id="788"> 788</span>
<span id="789"> 789</span>
<span id="790"> 790</span>
<span id="791"> 791</span>
<span id="792"> 792</span>
<span id="793"> 793</span>
<span id="794"> 794</span>
<span id="795"> 795</span>
<span id="796"> 796</span>
<span id="797"> 797</span>
<span id="798"> 798</span>
<span id="799"> 799</span>
<span id="800"> 800</span>
<span id="801"> 801</span>
<span id="802"> 802</span>
<span id="803"> 803</span>
<span id="804"> 804</span>
<span id="805"> 805</span>
<span id="806"> 806</span>
<span id="807"> 807</span>
<span id="808"> 808</span>
<span id="809"> 809</span>
<span id="810"> 810</span>
<span id="811"> 811</span>
<span id="812"> 812</span>
<span id="813"> 813</span>
<span id="814"> 814</span>
<span id="815"> 815</span>
<span id="816"> 816</span>
<span id="817"> 817</span>
<span id="818"> 818</span>
<span id="819"> 819</span>
<span id="820"> 820</span>
<span id="821"> 821</span>
<span id="822"> 822</span>
<span id="823"> 823</span>
<span id="824"> 824</span>
<span id="825"> 825</span>
<span id="826"> 826</span>
<span id="827"> 827</span>
<span id="828"> 828</span>
<span id="829"> 829</span>
<span id="830"> 830</span>
<span id="831"> 831</span>
<span id="832"> 832</span>
<span id="833"> 833</span>
<span id="834"> 834</span>
<span id="835"> 835</span>
<span id="836"> 836</span>
<span id="837"> 837</span>
<span id="838"> 838</span>
<span id="839"> 839</span>
<span id="840"> 840</span>
<span id="841"> 841</span>
<span id="842"> 842</span>
<span id="843"> 843</span>
<span id="844"> 844</span>
<span id="845"> 845</span>
<span id="846"> 846</span>
<span id="847"> 847</span>
<span id="848"> 848</span>
<span id="849"> 849</span>
<span id="850"> 850</span>
<span id="851"> 851</span>
<span id="852"> 852</span>
<span id="853"> 853</span>
<span id="854"> 854</span>
<span id="855"> 855</span>
<span id="856"> 856</span>
<span id="857"> 857</span>
<span id="858"> 858</span>
<span id="859"> 859</span>
<span id="860"> 860</span>
<span id="861"> 861</span>
<span id="862"> 862</span>
<span id="863"> 863</span>
<span id="864"> 864</span>
<span id="865"> 865</span>
<span id="866"> 866</span>
<span id="867"> 867</span>
<span id="868"> 868</span>
<span id="869"> 869</span>
<span id="870"> 870</span>
<span id="871"> 871</span>
<span id="872"> 872</span>
<span id="873"> 873</span>
<span id="874"> 874</span>
<span id="875"> 875</span>
<span id="876"> 876</span>
<span id="877"> 877</span>
<span id="878"> 878</span>
<span id="879"> 879</span>
<span id="880"> 880</span>
<span id="881"> 881</span>
<span id="882"> 882</span>
<span id="883"> 883</span>
<span id="884"> 884</span>
<span id="885"> 885</span>
<span id="886"> 886</span>
<span id="887"> 887</span>
<span id="888"> 888</span>
<span id="889"> 889</span>
<span id="890"> 890</span>
<span id="891"> 891</span>
<span id="892"> 892</span>
<span id="893"> 893</span>
<span id="894"> 894</span>
<span id="895"> 895</span>
<span id="896"> 896</span>
<span id="897"> 897</span>
<span id="898"> 898</span>
<span id="899"> 899</span>
<span id="900"> 900</span>
<span id="901"> 901</span>
<span id="902"> 902</span>
<span id="903"> 903</span>
<span id="904"> 904</span>
<span id="905"> 905</span>
<span id="906"> 906</span>
<span id="907"> 907</span>
<span id="908"> 908</span>
<span id="909"> 909</span>
<span id="910"> 910</span>
<span id="911"> 911</span>
<span id="912"> 912</span>
<span id="913"> 913</span>
<span id="914"> 914</span>
<span id="915"> 915</span>
<span id="916"> 916</span>
<span id="917"> 917</span>
<span id="918"> 918</span>
<span id="919"> 919</span>
<span id="920"> 920</span>
<span id="921"> 921</span>
<span id="922"> 922</span>
<span id="923"> 923</span>
<span id="924"> 924</span>
<span id="925"> 925</span>
<span id="926"> 926</span>
<span id="927"> 927</span>
<span id="928"> 928</span>
<span id="929"> 929</span>
<span id="930"> 930</span>
<span id="931"> 931</span>
<span id="932"> 932</span>
<span id="933"> 933</span>
<span id="934"> 934</span>
<span id="935"> 935</span>
<span id="936"> 936</span>
<span id="937"> 937</span>
<span id="938"> 938</span>
<span id="939"> 939</span>
<span id="940"> 940</span>
<span id="941"> 941</span>
<span id="942"> 942</span>
<span id="943"> 943</span>
<span id="944"> 944</span>
<span id="945"> 945</span>
<span id="946"> 946</span>
<span id="947"> 947</span>
<span id="948"> 948</span>
<span id="949"> 949</span>
<span id="950"> 950</span>
<span id="951"> 951</span>
<span id="952"> 952</span>
<span id="953"> 953</span>
<span id="954"> 954</span>
<span id="955"> 955</span>
<span id="956"> 956</span>
<span id="957"> 957</span>
<span id="958"> 958</span>
<span id="959"> 959</span>
<span id="960"> 960</span>
<span id="961"> 961</span>
<span id="962"> 962</span>
<span id="963"> 963</span>
<span id="964"> 964</span>
<span id="965"> 965</span>
<span id="966"> 966</span>
<span id="967"> 967</span>
<span id="968"> 968</span>
<span id="969"> 969</span>
<span id="970"> 970</span>
<span id="971"> 971</span>
<span id="972"> 972</span>
<span id="973"> 973</span>
<span id="974"> 974</span>
<span id="975"> 975</span>
<span id="976"> 976</span>
<span id="977"> 977</span>
<span id="978"> 978</span>
<span id="979"> 979</span>
<span id="980"> 980</span>
<span id="981"> 981</span>
<span id="982"> 982</span>
<span id="983"> 983</span>
<span id="984"> 984</span>
<span id="985"> 985</span>
<span id="986"> 986</span>
<span id="987"> 987</span>
<span id="988"> 988</span>
<span id="989"> 989</span>
<span id="990"> 990</span>
<span id="991"> 991</span>
<span id="992"> 992</span>
<span id="993"> 993</span>
<span id="994"> 994</span>
<span id="995"> 995</span>
<span id="996"> 996</span>
<span id="997"> 997</span>
<span id="998"> 998</span>
<span id="999"> 999</span>
<span id="1000">1000</span>
<span id="1001">1001</span>
<span id="1002">1002</span>
<span id="1003">1003</span>
<span id="1004">1004</span>
<span id="1005">1005</span>
<span id="1006">1006</span>
<span id="1007">1007</span>
<span id="1008">1008</span>
<span id="1009">1009</span>
<span id="1010">1010</span>
<span id="1011">1011</span>
<span id="1012">1012</span>
<span id="1013">1013</span>
<span id="1014">1014</span>
<span id="1015">1015</span>
<span id="1016">1016</span>
<span id="1017">1017</span>
<span id="1018">1018</span>
<span id="1019">1019</span>
<span id="1020">1020</span>
<span id="1021">1021</span>
<span id="1022">1022</span>
<span id="1023">1023</span>
<span id="1024">1024</span>
<span id="1025">1025</span>
<span id="1026">1026</span>
<span id="1027">1027</span>
<span id="1028">1028</span>
<span id="1029">1029</span>
<span id="1030">1030</span>
<span id="1031">1031</span>
<span id="1032">1032</span>
<span id="1033">1033</span>
<span id="1034">1034</span>
<span id="1035">1035</span>
<span id="1036">1036</span>
<span id="1037">1037</span>
<span id="1038">1038</span>
<span id="1039">1039</span>
<span id="1040">1040</span>
<span id="1041">1041</span>
<span id="1042">1042</span>
<span id="1043">1043</span>
<span id="1044">1044</span>
<span id="1045">1045</span>
<span id="1046">1046</span>
<span id="1047">1047</span>
<span id="1048">1048</span>
<span id="1049">1049</span>
<span id="1050">1050</span>
<span id="1051">1051</span>
<span id="1052">1052</span>
<span id="1053">1053</span>
<span id="1054">1054</span>
<span id="1055">1055</span>
<span id="1056">1056</span>
<span id="1057">1057</span>
<span id="1058">1058</span>
<span id="1059">1059</span>
<span id="1060">1060</span>
<span id="1061">1061</span>
<span id="1062">1062</span>
<span id="1063">1063</span>
<span id="1064">1064</span>
<span id="1065">1065</span>
<span id="1066">1066</span>
<span id="1067">1067</span>
<span id="1068">1068</span>
<span id="1069">1069</span>
<span id="1070">1070</span>
<span id="1071">1071</span>
<span id="1072">1072</span>
<span id="1073">1073</span>
<span id="1074">1074</span>
<span id="1075">1075</span>
<span id="1076">1076</span>
<span id="1077">1077</span>
<span id="1078">1078</span>
<span id="1079">1079</span>
<span id="1080">1080</span>
<span id="1081">1081</span>
<span id="1082">1082</span>
<span id="1083">1083</span>
<span id="1084">1084</span>
<span id="1085">1085</span>
<span id="1086">1086</span>
<span id="1087">1087</span>
<span id="1088">1088</span>
<span id="1089">1089</span>
<span id="1090">1090</span>
<span id="1091">1091</span>
<span id="1092">1092</span>
<span id="1093">1093</span>
<span id="1094">1094</span>
<span id="1095">1095</span>
<span id="1096">1096</span>
<span id="1097">1097</span>
<span id="1098">1098</span>
<span id="1099">1099</span>
<span id="1100">1100</span>
</pre><pre class="rust ">
<span class="comment">// Copyright 2015 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 &lt;LICENSE-APACHE or</span>
<span class="comment">// http://www.apache.org/licenses/LICENSE-2.0&gt; or the MIT license</span>
<span class="comment">// &lt;LICENSE-MIT or http://opensource.org/licenses/MIT&gt;, 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="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;bool&quot;</span>)]</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">alias</span> <span class="op">=</span> <span class="string">&quot;true&quot;</span>)]</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">alias</span> <span class="op">=</span> <span class="string">&quot;false&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The boolean type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The `bool` represents a value, which could only be either `true` or `false`. If you cast</span>
<span class="doccomment">/// a `bool` into an integer, `true` will be 1 and `false` will be 0.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Basic usage</span>
<span class="doccomment">///</span>
<span class="doccomment">/// `bool` implements various traits, such as [`BitAnd`], [`BitOr`], [`Not`], etc.,</span>
<span class="doccomment">/// which allow us to perform boolean operations using `&amp;`, `|` and `!`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`if`] always demands a `bool` value. [`assert!`], being an important macro in testing,</span>
<span class="doccomment">/// checks whether an expression returns `true`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let bool_val = true &amp; false | false;</span>
<span class="doccomment">/// assert!(!bool_val);</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`assert!`]: macro.assert.html</span>
<span class="doccomment">/// [`if`]: ../book/first-edition/if.html</span>
<span class="doccomment">/// [`BitAnd`]: ops/trait.BitAnd.html</span>
<span class="doccomment">/// [`BitOr`]: ops/trait.BitOr.html</span>
<span class="doccomment">/// [`Not`]: ops/trait.Not.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// A trivial example of the usage of `bool`,</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let praise_the_borrow_checker = true;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // using the `if` conditional</span>
<span class="doccomment">/// if praise_the_borrow_checker {</span>
<span class="doccomment">///     println!(&quot;oh, yeah!&quot;);</span>
<span class="doccomment">/// } else {</span>
<span class="doccomment">///     println!(&quot;what?!!&quot;);</span>
<span class="doccomment">/// }</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // ... or, a match pattern</span>
<span class="doccomment">/// match praise_the_borrow_checker {</span>
<span class="doccomment">///     true =&gt; println!(&quot;keep praising!&quot;),</span>
<span class="doccomment">///     false =&gt; println!(&quot;you should praise!&quot;),</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Also, since `bool` implements the [`Copy`](marker/trait.Copy.html) trait, we don&#39;t</span>
<span class="doccomment">/// have to worry about the move semantics (just like the integer and float primitives).</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Now an example of `bool` cast to integer type:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// assert_eq!(true as i32, 1);</span>
<span class="doccomment">/// assert_eq!(false as i32, 0);</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">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_bool</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;never&quot;</span>)]</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">alias</span> <span class="op">=</span> <span class="string">&quot;!&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The `!` type, also called &quot;never&quot;.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// `!` represents the type of computations which never resolve to any value at all. For example,</span>
<span class="doccomment">/// the [`exit`] function `fn exit(code: i32) -&gt; !` exits the process without ever returning, and</span>
<span class="doccomment">/// so returns `!`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// `break`, `continue` and `return` expressions also have type `!`. For example we are allowed to</span>
<span class="doccomment">/// write:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// #![feature(never_type)]</span>
<span class="doccomment">/// # fn foo() -&gt; u32 {</span>
<span class="doccomment">/// let x: ! = {</span>
<span class="doccomment">///     return 123</span>
<span class="doccomment">/// };</span>
<span class="doccomment">/// # }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Although the `let` is pointless here, it illustrates the meaning of `!`. Since `x` is never</span>
<span class="doccomment">/// assigned a value (because `return` returns from the entire function), `x` can be given type</span>
<span class="doccomment">/// `!`. We could also replace `return 123` with a `panic!` or a never-ending `loop` and this code</span>
<span class="doccomment">/// would still be valid.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// A more realistic usage of `!` is in this code:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// # fn get_a_number() -&gt; Option&lt;u32&gt; { None }</span>
<span class="doccomment">/// # loop {</span>
<span class="doccomment">/// let num: u32 = match get_a_number() {</span>
<span class="doccomment">///     Some(num) =&gt; num,</span>
<span class="doccomment">///     None =&gt; break,</span>
<span class="doccomment">/// };</span>
<span class="doccomment">/// # }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Both match arms must produce values of type [`u32`], but since `break` never produces a value</span>
<span class="doccomment">/// at all we know it can never produce a value which isn&#39;t a [`u32`]. This illustrates another</span>
<span class="doccomment">/// behaviour of the `!` type - expressions with type `!` will coerce into any other type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`u32`]: primitive.str.html</span>
<span class="doccomment">/// [`exit`]: process/fn.exit.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # `!` and generics</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ## Infallible errors</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The main place you&#39;ll see `!` used explicitly is in generic code. Consider the [`FromStr`]</span>
<span class="doccomment">/// trait:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// trait FromStr: Sized {</span>
<span class="doccomment">///     type Err;</span>
<span class="doccomment">///     fn from_str(s: &amp;str) -&gt; Result&lt;Self, Self::Err&gt;;</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// When implementing this trait for [`String`] we need to pick a type for [`Err`]. And since</span>
<span class="doccomment">/// converting a string into a string will never result in an error, the appropriate type is `!`.</span>
<span class="doccomment">/// (Currently the type actually used is an enum with no variants, though this is only because `!`</span>
<span class="doccomment">/// was added to Rust at a later date and it may change in the future). With an [`Err`] type of</span>
<span class="doccomment">/// `!`, if we have to call [`String::from_str`] for some reason the result will be a</span>
<span class="doccomment">/// [`Result&lt;String, !&gt;`] which we can unpack like this:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```ignore (string-from-str-error-type-is-not-never-yet)</span>
<span class="doccomment">/// #[feature(exhaustive_patterns)]</span>
<span class="doccomment">/// // NOTE: This does not work today!</span>
<span class="doccomment">/// let Ok(s) = String::from_str(&quot;hello&quot;);</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Since the [`Err`] variant contains a `!`, it can never occur. If the `exhaustive_patterns`</span>
<span class="doccomment">/// feature is present this means we can exhaustively match on [`Result&lt;T, !&gt;`] by just taking the</span>
<span class="doccomment">/// [`Ok`] variant. This illustrates another behaviour of `!` - it can be used to &quot;delete&quot; certain</span>
<span class="doccomment">/// enum variants from generic types like `Result`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ## Infinite loops</span>
<span class="doccomment">///</span>
<span class="doccomment">/// While [`Result&lt;T, !&gt;`] is very useful for removing errors, `!` can also be used to remove</span>
<span class="doccomment">/// successes as well. If we think of [`Result&lt;T, !&gt;`] as &quot;if this function returns, it has not</span>
<span class="doccomment">/// errored,&quot; we get a very intuitive idea of [`Result&lt;!, E&gt;`] as well: if the function returns, it</span>
<span class="doccomment">/// *has* errored.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// For example, consider the case of a simple web server, which can be simplified to:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```ignore (hypothetical-example)</span>
<span class="doccomment">/// loop {</span>
<span class="doccomment">///     let (client, request) = get_request().expect(&quot;disconnected&quot;);</span>
<span class="doccomment">///     let response = request.process();</span>
<span class="doccomment">///     response.send(client);</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Currently, this isn&#39;t ideal, because we simply panic whenever we fail to get a new connection.</span>
<span class="doccomment">/// Instead, we&#39;d like to keep track of this error, like this:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```ignore (hypothetical-example)</span>
<span class="doccomment">/// loop {</span>
<span class="doccomment">///     match get_request() {</span>
<span class="doccomment">///         Err(err) =&gt; break err,</span>
<span class="doccomment">///         Ok((client, request)) =&gt; {</span>
<span class="doccomment">///             let response = request.process();</span>
<span class="doccomment">///             response.send(client);</span>
<span class="doccomment">///         },</span>
<span class="doccomment">///     }</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Now, when the server disconnects, we exit the loop with an error instead of panicking. While it</span>
<span class="doccomment">/// might be intuitive to simply return the error, we might want to wrap it in a [`Result&lt;!, E&gt;`]</span>
<span class="doccomment">/// instead:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```ignore (hypothetical-example)</span>
<span class="doccomment">/// fn server_loop() -&gt; Result&lt;!, ConnectionError&gt; {</span>
<span class="doccomment">///     loop {</span>
<span class="doccomment">///         let (client, request) = get_request()?;</span>
<span class="doccomment">///         let response = request.process();</span>
<span class="doccomment">///         response.send(client);</span>
<span class="doccomment">///     }</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Now, we can use `?` instead of `match`, and the return type makes a lot more sense: if the loop</span>
<span class="doccomment">/// ever stops, it means that an error occurred. We don&#39;t even have to wrap the loop in an `Ok`</span>
<span class="doccomment">/// because `!` coerces to `Result&lt;!, ConnectionError&gt;` automatically.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`String::from_str`]: str/trait.FromStr.html#tymethod.from_str</span>
<span class="doccomment">/// [`Result&lt;String, !&gt;`]: result/enum.Result.html</span>
<span class="doccomment">/// [`Result&lt;T, !&gt;`]: result/enum.Result.html</span>
<span class="doccomment">/// [`Result&lt;!, E&gt;`]: result/enum.Result.html</span>
<span class="doccomment">/// [`Ok`]: result/enum.Result.html#variant.Ok</span>
<span class="doccomment">/// [`String`]: string/struct.String.html</span>
<span class="doccomment">/// [`Err`]: result/enum.Result.html#variant.Err</span>
<span class="doccomment">/// [`FromStr`]: str/trait.FromStr.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # `!` and traits</span>
<span class="doccomment">///</span>
<span class="doccomment">/// When writing your own traits, `!` should have an `impl` whenever there is an obvious `impl`</span>
<span class="doccomment">/// which doesn&#39;t `panic!`. As is turns out, most traits can have an `impl` for `!`. Take [`Debug`]</span>
<span class="doccomment">/// for example:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// #![feature(never_type)]</span>
<span class="doccomment">/// # use std::fmt;</span>
<span class="doccomment">/// # trait Debug {</span>
<span class="doccomment">/// # fn fmt(&amp;self, formatter: &amp;mut fmt::Formatter) -&gt; fmt::Result;</span>
<span class="doccomment">/// # }</span>
<span class="doccomment">/// impl Debug for ! {</span>
<span class="doccomment">///     fn fmt(&amp;self, formatter: &amp;mut fmt::Formatter) -&gt; fmt::Result {</span>
<span class="doccomment">///         *self</span>
<span class="doccomment">///     }</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Once again we&#39;re using `!`&#39;s ability to coerce into any other type, in this case</span>
<span class="doccomment">/// [`fmt::Result`]. Since this method takes a `&amp;!` as an argument we know that it can never be</span>
<span class="doccomment">/// called (because there is no value of type `!` for it to be called with). Writing `*self`</span>
<span class="doccomment">/// essentially tells the compiler &quot;We know that this code can never be run, so just treat the</span>
<span class="doccomment">/// entire function body has having type [`fmt::Result`]&quot;. This pattern can be used a lot when</span>
<span class="doccomment">/// implementing traits for `!`. Generally, any trait which only has methods which take a `self`</span>
<span class="doccomment">/// parameter should have such as impl.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// On the other hand, one trait which would not be appropriate to implement is [`Default`]:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// trait Default {</span>
<span class="doccomment">///     fn default() -&gt; Self;</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Since `!` has no values, it has no default value either. It&#39;s true that we could write an</span>
<span class="doccomment">/// `impl` for this which simply panics, but the same is true for any type (we could `impl</span>
<span class="doccomment">/// Default` for (eg.) [`File`] by just making [`default()`] panic.)</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`fmt::Result`]: fmt/type.Result.html</span>
<span class="doccomment">/// [`File`]: fs/struct.File.html</span>
<span class="doccomment">/// [`Debug`]: fmt/trait.Debug.html</span>
<span class="doccomment">/// [`Default`]: default/trait.Default.html</span>
<span class="doccomment">/// [`default()`]: default/trait.Default.html#tymethod.default</span>
<span class="doccomment">///</span>
<span class="kw">mod</span> <span class="ident">prim_never</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;char&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// A character type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The `char` type represents a single character. More specifically, since</span>
<span class="doccomment">/// &#39;character&#39; isn&#39;t a well-defined concept in Unicode, `char` is a &#39;[Unicode</span>
<span class="doccomment">/// scalar value]&#39;, which is similar to, but not the same as, a &#39;[Unicode code</span>
<span class="doccomment">/// point]&#39;.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [Unicode scalar value]: http://www.unicode.org/glossary/#unicode_scalar_value</span>
<span class="doccomment">/// [Unicode code point]: http://www.unicode.org/glossary/#code_point</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This documentation describes a number of methods and trait implementations on the</span>
<span class="doccomment">/// `char` type. For technical reasons, there is additional, separate</span>
<span class="doccomment">/// documentation in [the `std::char` module](char/index.html) as well.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Representation</span>
<span class="doccomment">///</span>
<span class="doccomment">/// `char` is always four bytes in size. This is a different representation than</span>
<span class="doccomment">/// a given character would have as part of a [`String`]. For example:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let v = vec![&#39;h&#39;, &#39;e&#39;, &#39;l&#39;, &#39;l&#39;, &#39;o&#39;];</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // five elements times four bytes for each element</span>
<span class="doccomment">/// assert_eq!(20, v.len() * std::mem::size_of::&lt;char&gt;());</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let s = String::from(&quot;hello&quot;);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // five elements times one byte per element</span>
<span class="doccomment">/// assert_eq!(5, s.len() * std::mem::size_of::&lt;u8&gt;());</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`String`]: string/struct.String.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// As always, remember that a human intuition for &#39;character&#39; may not map to</span>
<span class="doccomment">/// Unicode&#39;s definitions. For example, despite looking similar, the &#39;é&#39;</span>
<span class="doccomment">/// character is one Unicode code point while &#39;é&#39; is two Unicode code points:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let mut chars = &quot;é&quot;.chars();</span>
<span class="doccomment">/// // U+00e9: &#39;latin small letter e with acute&#39;</span>
<span class="doccomment">/// assert_eq!(Some(&#39;\u{00e9}&#39;), chars.next());</span>
<span class="doccomment">/// assert_eq!(None, chars.next());</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let mut chars = &quot;é&quot;.chars();</span>
<span class="doccomment">/// // U+0065: &#39;latin small letter e&#39;</span>
<span class="doccomment">/// assert_eq!(Some(&#39;\u{0065}&#39;), chars.next());</span>
<span class="doccomment">/// // U+0301: &#39;combining acute accent&#39;</span>
<span class="doccomment">/// assert_eq!(Some(&#39;\u{0301}&#39;), chars.next());</span>
<span class="doccomment">/// assert_eq!(None, chars.next());</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This means that the contents of the first string above _will_ fit into a</span>
<span class="doccomment">/// `char` while the contents of the second string _will not_. Trying to create</span>
<span class="doccomment">/// a `char` literal with the contents of the second string gives an error:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```text</span>
<span class="doccomment">/// error: character literal may only contain one codepoint: &#39;é&#39;</span>
<span class="doccomment">/// let c = &#39;é&#39;;</span>
<span class="doccomment">///         ^^^^</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Another implication of the 4-byte fixed size of a `char` is that</span>
<span class="doccomment">/// per-`char` processing can end up using a lot more memory:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let s = String::from(&quot;love: ❤️&quot;);</span>
<span class="doccomment">/// let v: Vec&lt;char&gt; = s.chars().collect();</span>
<span class="doccomment">///</span>
<span class="doccomment">/// assert_eq!(12, s.len() * std::mem::size_of::&lt;u8&gt;());</span>
<span class="doccomment">/// assert_eq!(32, v.len() * std::mem::size_of::&lt;char&gt;());</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">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_char</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;unit&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The `()` type, sometimes called &quot;unit&quot; or &quot;nil&quot;.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The `()` type has exactly one value `()`, and is used when there</span>
<span class="doccomment">/// is no other meaningful value that could be returned. `()` is most</span>
<span class="doccomment">/// commonly seen implicitly: functions without a `-&gt; ...` implicitly</span>
<span class="doccomment">/// have return type `()`, that is, these are equivalent:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```rust</span>
<span class="doccomment">/// fn long() -&gt; () {}</span>
<span class="doccomment">///</span>
<span class="doccomment">/// fn short() {}</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The semicolon `;` can be used to discard the result of an</span>
<span class="doccomment">/// expression at the end of a block, making the expression (and thus</span>
<span class="doccomment">/// the block) evaluate to `()`. For example,</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```rust</span>
<span class="doccomment">/// fn returns_i64() -&gt; i64 {</span>
<span class="doccomment">///     1i64</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// fn returns_unit() {</span>
<span class="doccomment">///     1i64;</span>
<span class="doccomment">/// }</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let is_i64 = {</span>
<span class="doccomment">///     returns_i64()</span>
<span class="doccomment">/// };</span>
<span class="doccomment">/// let is_unit = {</span>
<span class="doccomment">///     returns_i64();</span>
<span class="doccomment">/// };</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">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_unit</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;pointer&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// Raw, unsafe pointers, `*const T`, and `*mut T`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::ptr` module](ptr/index.html).*</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Working with raw pointers in Rust is uncommon,</span>
<span class="doccomment">/// typically limited to a few patterns.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Use the [`null`] and [`null_mut`] functions to create null pointers, and the</span>
<span class="doccomment">/// [`is_null`] method of the `*const T` and `*mut T` types to check for null.</span>
<span class="doccomment">/// The `*const T` and `*mut T` types also define the [`offset`] method, for</span>
<span class="doccomment">/// pointer math.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Common ways to create raw pointers</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ## 1. Coerce a reference (`&amp;T`) or mutable reference (`&amp;mut T`).</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let my_num: i32 = 10;</span>
<span class="doccomment">/// let my_num_ptr: *const i32 = &amp;my_num;</span>
<span class="doccomment">/// let mut my_speed: i32 = 88;</span>
<span class="doccomment">/// let my_speed_ptr: *mut i32 = &amp;mut my_speed;</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// To get a pointer to a boxed value, dereference the box:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let my_num: Box&lt;i32&gt; = Box::new(10);</span>
<span class="doccomment">/// let my_num_ptr: *const i32 = &amp;*my_num;</span>
<span class="doccomment">/// let mut my_speed: Box&lt;i32&gt; = Box::new(88);</span>
<span class="doccomment">/// let my_speed_ptr: *mut i32 = &amp;mut *my_speed;</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This does not take ownership of the original allocation</span>
<span class="doccomment">/// and requires no resource management later,</span>
<span class="doccomment">/// but you must not use the pointer after its lifetime.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ## 2. Consume a box (`Box&lt;T&gt;`).</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The [`into_raw`] function consumes a box and returns</span>
<span class="doccomment">/// the raw pointer. It doesn&#39;t destroy `T` or deallocate any memory.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let my_speed: Box&lt;i32&gt; = Box::new(88);</span>
<span class="doccomment">/// let my_speed: *mut i32 = Box::into_raw(my_speed);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // By taking ownership of the original `Box&lt;T&gt;` though</span>
<span class="doccomment">/// // we are obligated to put it together later to be destroyed.</span>
<span class="doccomment">/// unsafe {</span>
<span class="doccomment">///     drop(Box::from_raw(my_speed));</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Note that here the call to [`drop`] is for clarity - it indicates</span>
<span class="doccomment">/// that we are done with the given value and it should be destroyed.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ## 3. Get it from C.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// # #![feature(libc)]</span>
<span class="doccomment">/// extern crate libc;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// use std::mem;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// fn main() {</span>
<span class="doccomment">///     unsafe {</span>
<span class="doccomment">///         let my_num: *mut i32 = libc::malloc(mem::size_of::&lt;i32&gt;()) as *mut i32;</span>
<span class="doccomment">///         if my_num.is_null() {</span>
<span class="doccomment">///             panic!(&quot;failed to allocate memory&quot;);</span>
<span class="doccomment">///         }</span>
<span class="doccomment">///         libc::free(my_num as *mut libc::c_void);</span>
<span class="doccomment">///     }</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Usually you wouldn&#39;t literally use `malloc` and `free` from Rust,</span>
<span class="doccomment">/// but C APIs hand out a lot of pointers generally, so are a common source</span>
<span class="doccomment">/// of raw pointers in Rust.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`null`]: ../std/ptr/fn.null.html</span>
<span class="doccomment">/// [`null_mut`]: ../std/ptr/fn.null_mut.html</span>
<span class="doccomment">/// [`is_null`]: ../std/primitive.pointer.html#method.is_null</span>
<span class="doccomment">/// [`offset`]: ../std/primitive.pointer.html#method.offset</span>
<span class="doccomment">/// [`into_raw`]: ../std/boxed/struct.Box.html#method.into_raw</span>
<span class="doccomment">/// [`drop`]: ../std/mem/fn.drop.html</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_pointer</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;array&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// A fixed-size array, denoted `[T; N]`, for the element type, `T`, and the</span>
<span class="doccomment">/// non-negative compile-time constant size, `N`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// There are two syntactic forms for creating an array:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// * A list with each element, i.e. `[x, y, z]`.</span>
<span class="doccomment">/// * A repeat expression `[x; N]`, which produces an array with `N` copies of `x`.</span>
<span class="doccomment">///   The type of `x` must be [`Copy`][copy].</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Arrays of sizes from 0 to 32 (inclusive) implement the following traits if</span>
<span class="doccomment">/// the element type allows it:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// - [`Debug`][debug]</span>
<span class="doccomment">/// - [`IntoIterator`][intoiterator] (implemented for `&amp;[T; N]` and `&amp;mut [T; N]`)</span>
<span class="doccomment">/// - [`PartialEq`][partialeq], [`PartialOrd`][partialord], [`Eq`][eq], [`Ord`][ord]</span>
<span class="doccomment">/// - [`Hash`][hash]</span>
<span class="doccomment">/// - [`AsRef`][asref], [`AsMut`][asmut]</span>
<span class="doccomment">/// - [`Borrow`][borrow], [`BorrowMut`][borrowmut]</span>
<span class="doccomment">/// - [`Default`][default]</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This limitation on the size `N` exists because Rust does not yet support</span>
<span class="doccomment">/// code that is generic over the size of an array type. `[Foo; 3]` and `[Bar; 3]`</span>
<span class="doccomment">/// are instances of same generic type `[T; 3]`, but `[Foo; 3]` and `[Foo; 5]` are</span>
<span class="doccomment">/// entirely different types. As a stopgap, trait implementations are</span>
<span class="doccomment">/// statically generated up to size 32.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Arrays of *any* size are [`Copy`][copy] if the element type is [`Copy`][copy]</span>
<span class="doccomment">/// and [`Clone`][clone] if the element type is [`Clone`][clone]. This works</span>
<span class="doccomment">/// because [`Copy`][copy] and [`Clone`][clone] traits are specially known</span>
<span class="doccomment">/// to the compiler.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Arrays coerce to [slices (`[T]`)][slice], so a slice method may be called on</span>
<span class="doccomment">/// an array. Indeed, this provides most of the API for working with arrays.</span>
<span class="doccomment">/// Slices have a dynamic size and do not coerce to arrays.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// There is no way to move elements out of an array. See [`mem::replace`][replace]</span>
<span class="doccomment">/// for an alternative.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let mut array: [i32; 3] = [0; 3];</span>
<span class="doccomment">///</span>
<span class="doccomment">/// array[1] = 1;</span>
<span class="doccomment">/// array[2] = 2;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// assert_eq!([1, 2], &amp;array[1..]);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // This loop prints: 0 1 2</span>
<span class="doccomment">/// for x in &amp;array {</span>
<span class="doccomment">///     print!(&quot;{} &quot;, x);</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// An array itself is not iterable:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```compile_fail,E0277</span>
<span class="doccomment">/// let array: [i32; 3] = [0; 3];</span>
<span class="doccomment">///</span>
<span class="doccomment">/// for x in array { }</span>
<span class="doccomment">/// // error: the trait bound `[i32; 3]: std::iter::Iterator` is not satisfied</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The solution is to coerce the array to a slice by calling a slice method:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// # let array: [i32; 3] = [0; 3];</span>
<span class="doccomment">/// for x in array.iter() { }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// If the array has 32 or fewer elements (see above), you can also use the</span>
<span class="doccomment">/// array reference&#39;s [`IntoIterator`] implementation:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// # let array: [i32; 3] = [0; 3];</span>
<span class="doccomment">/// for x in &amp;array { }</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [slice]: primitive.slice.html</span>
<span class="doccomment">/// [copy]: marker/trait.Copy.html</span>
<span class="doccomment">/// [clone]: clone/trait.Clone.html</span>
<span class="doccomment">/// [debug]: fmt/trait.Debug.html</span>
<span class="doccomment">/// [intoiterator]: iter/trait.IntoIterator.html</span>
<span class="doccomment">/// [partialeq]: cmp/trait.PartialEq.html</span>
<span class="doccomment">/// [partialord]: cmp/trait.PartialOrd.html</span>
<span class="doccomment">/// [eq]: cmp/trait.Eq.html</span>
<span class="doccomment">/// [ord]: cmp/trait.Ord.html</span>
<span class="doccomment">/// [hash]: hash/trait.Hash.html</span>
<span class="doccomment">/// [asref]: convert/trait.AsRef.html</span>
<span class="doccomment">/// [asmut]: convert/trait.AsMut.html</span>
<span class="doccomment">/// [borrow]: borrow/trait.Borrow.html</span>
<span class="doccomment">/// [borrowmut]: borrow/trait.BorrowMut.html</span>
<span class="doccomment">/// [default]: default/trait.Default.html</span>
<span class="doccomment">/// [replace]: mem/fn.replace.html</span>
<span class="doccomment">/// [`IntoIterator`]: iter/trait.IntoIterator.html</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">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_array</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;slice&quot;</span>)]</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">alias</span> <span class="op">=</span> <span class="string">&quot;[&quot;</span>)]</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">alias</span> <span class="op">=</span> <span class="string">&quot;]&quot;</span>)]</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">alias</span> <span class="op">=</span> <span class="string">&quot;[]&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// A dynamically-sized view into a contiguous sequence, `[T]`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::slice` module](slice/index.html).*</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Slices are a view into a block of memory represented as a pointer and a</span>
<span class="doccomment">/// length.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// // slicing a Vec</span>
<span class="doccomment">/// let vec = vec![1, 2, 3];</span>
<span class="doccomment">/// let int_slice = &amp;vec[..];</span>
<span class="doccomment">/// // coercing an array to a slice</span>
<span class="doccomment">/// let str_slice: &amp;[&amp;str] = &amp;[&quot;one&quot;, &quot;two&quot;, &quot;three&quot;];</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Slices are either mutable or shared. The shared slice type is `&amp;[T]`,</span>
<span class="doccomment">/// while the mutable slice type is `&amp;mut [T]`, where `T` represents the element</span>
<span class="doccomment">/// type. For example, you can mutate the block of memory that a mutable slice</span>
<span class="doccomment">/// points to:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let x = &amp;mut [1, 2, 3];</span>
<span class="doccomment">/// x[1] = 7;</span>
<span class="doccomment">/// assert_eq!(x, &amp;[1, 7, 3]);</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">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_slice</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;str&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// String slices.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::str` module](str/index.html).*</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The `str` type, also called a &#39;string slice&#39;, is the most primitive string</span>
<span class="doccomment">/// type. It is usually seen in its borrowed form, `&amp;str`. It is also the type</span>
<span class="doccomment">/// of string literals, `&amp;&#39;static str`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// String slices are always valid UTF-8.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// String literals are string slices:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// let hello = &quot;Hello, world!&quot;;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // with an explicit type annotation</span>
<span class="doccomment">/// let hello: &amp;&#39;static str = &quot;Hello, world!&quot;;</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// They are `&#39;static` because they&#39;re stored directly in the final binary, and</span>
<span class="doccomment">/// so will be valid for the `&#39;static` duration.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Representation</span>
<span class="doccomment">///</span>
<span class="doccomment">/// A `&amp;str` is made up of two components: a pointer to some bytes, and a</span>
<span class="doccomment">/// length. You can look at these with the [`as_ptr`] and [`len`] methods:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// use std::slice;</span>
<span class="doccomment">/// use std::str;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let story = &quot;Once upon a time...&quot;;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let ptr = story.as_ptr();</span>
<span class="doccomment">/// let len = story.len();</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // story has nineteen bytes</span>
<span class="doccomment">/// assert_eq!(19, len);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // We can re-build a str out of ptr and len. This is all unsafe because</span>
<span class="doccomment">/// // we are responsible for making sure the two components are valid:</span>
<span class="doccomment">/// let s = unsafe {</span>
<span class="doccomment">///     // First, we build a &amp;[u8]...</span>
<span class="doccomment">///     let slice = slice::from_raw_parts(ptr, len);</span>
<span class="doccomment">///</span>
<span class="doccomment">///     // ... and then convert that slice into a string slice</span>
<span class="doccomment">///     str::from_utf8(slice)</span>
<span class="doccomment">/// };</span>
<span class="doccomment">///</span>
<span class="doccomment">/// assert_eq!(s, Ok(story));</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`as_ptr`]: #method.as_ptr</span>
<span class="doccomment">/// [`len`]: #method.len</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Note: This example shows the internals of `&amp;str`. `unsafe` should not be</span>
<span class="doccomment">/// used to get a string slice under normal circumstances. Use `as_slice`</span>
<span class="doccomment">/// instead.</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_str</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;tuple&quot;</span>)]</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">alias</span> <span class="op">=</span> <span class="string">&quot;(&quot;</span>)]</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">alias</span> <span class="op">=</span> <span class="string">&quot;)&quot;</span>)]</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">alias</span> <span class="op">=</span> <span class="string">&quot;()&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// A finite heterogeneous sequence, `(T, U, ..)`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Let&#39;s cover each of those in turn:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Tuples are *finite*. In other words, a tuple has a length. Here&#39;s a tuple</span>
<span class="doccomment">/// of length `3`:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// (&quot;hello&quot;, 5, &#39;c&#39;);</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// &#39;Length&#39; is also sometimes called &#39;arity&#39; here; each tuple of a different</span>
<span class="doccomment">/// length is a different, distinct type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Tuples are *heterogeneous*. This means that each element of the tuple can</span>
<span class="doccomment">/// have a different type. In that tuple above, it has the type:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// # let _:</span>
<span class="doccomment">/// (&amp;&#39;static str, i32, char)</span>
<span class="doccomment">/// # = (&quot;hello&quot;, 5, &#39;c&#39;);</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Tuples are a *sequence*. This means that they can be accessed by position;</span>
<span class="doccomment">/// this is called &#39;tuple indexing&#39;, and it looks like this:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```rust</span>
<span class="doccomment">/// let tuple = (&quot;hello&quot;, 5, &#39;c&#39;);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// assert_eq!(tuple.0, &quot;hello&quot;);</span>
<span class="doccomment">/// assert_eq!(tuple.1, 5);</span>
<span class="doccomment">/// assert_eq!(tuple.2, &#39;c&#39;);</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// For more about tuples, see [the book](../book/first-edition/primitive-types.html#tuples).</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Trait implementations</span>
<span class="doccomment">///</span>
<span class="doccomment">/// If every type inside a tuple implements one of the following traits, then a</span>
<span class="doccomment">/// tuple itself also implements it.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// * [`Clone`]</span>
<span class="doccomment">/// * [`Copy`]</span>
<span class="doccomment">/// * [`PartialEq`]</span>
<span class="doccomment">/// * [`Eq`]</span>
<span class="doccomment">/// * [`PartialOrd`]</span>
<span class="doccomment">/// * [`Ord`]</span>
<span class="doccomment">/// * [`Debug`]</span>
<span class="doccomment">/// * [`Default`]</span>
<span class="doccomment">/// * [`Hash`]</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`Clone`]: clone/trait.Clone.html</span>
<span class="doccomment">/// [`Copy`]: marker/trait.Copy.html</span>
<span class="doccomment">/// [`PartialEq`]: cmp/trait.PartialEq.html</span>
<span class="doccomment">/// [`Eq`]: cmp/trait.Eq.html</span>
<span class="doccomment">/// [`PartialOrd`]: cmp/trait.PartialOrd.html</span>
<span class="doccomment">/// [`Ord`]: cmp/trait.Ord.html</span>
<span class="doccomment">/// [`Debug`]: fmt/trait.Debug.html</span>
<span class="doccomment">/// [`Default`]: default/trait.Default.html</span>
<span class="doccomment">/// [`Hash`]: hash/trait.Hash.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Due to a temporary restriction in Rust&#39;s type system, these traits are only</span>
<span class="doccomment">/// implemented on tuples of arity 12 or less. In the future, this may change.</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 tuple = (&quot;hello&quot;, 5, &#39;c&#39;);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// assert_eq!(tuple.0, &quot;hello&quot;);</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Tuples are often used as a return type when you want to return more than</span>
<span class="doccomment">/// one value:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// fn calculate_point() -&gt; (i32, i32) {</span>
<span class="doccomment">///     // Don&#39;t do a calculation, that&#39;s not the point of the example</span>
<span class="doccomment">///     (4, 5)</span>
<span class="doccomment">/// }</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let point = calculate_point();</span>
<span class="doccomment">///</span>
<span class="doccomment">/// assert_eq!(point.0, 4);</span>
<span class="doccomment">/// assert_eq!(point.1, 5);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // Combining this with patterns can be nicer.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let (x, y) = calculate_point();</span>
<span class="doccomment">///</span>
<span class="doccomment">/// assert_eq!(x, 4);</span>
<span class="doccomment">/// assert_eq!(y, 5);</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">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_tuple</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;f32&quot;</span>)]</span>
<span class="doccomment">/// The 32-bit floating point type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::f32` module](f32/index.html).*</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">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_f32</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;f64&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 64-bit floating point type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::f64` module](f64/index.html).*</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">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_f64</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;i8&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 8-bit signed integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::i8` module](i8/index.html).*</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_i8</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;i16&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 16-bit signed integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::i16` module](i16/index.html).*</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_i16</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;i32&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 32-bit signed integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::i32` module](i32/index.html).*</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_i32</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;i64&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 64-bit signed integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::i64` module](i64/index.html).*</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_i64</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;i128&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 128-bit signed integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::i128` module](i128/index.html).*</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;i128&quot;</span>, <span class="ident">since</span><span class="op">=</span><span class="string">&quot;1.26.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_i128</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;u8&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 8-bit unsigned integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::u8` module](u8/index.html).*</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_u8</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;u16&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 16-bit unsigned integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::u16` module](u16/index.html).*</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_u16</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;u32&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 32-bit unsigned integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::u32` module](u32/index.html).*</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_u32</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;u64&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 64-bit unsigned integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::u64` module](u64/index.html).*</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_u64</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;u128&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The 128-bit unsigned integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::u128` module](u128/index.html).*</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;i128&quot;</span>, <span class="ident">since</span><span class="op">=</span><span class="string">&quot;1.26.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_u128</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;isize&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The pointer-sized signed integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::isize` module](isize/index.html).*</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The size of this primitive is how many bytes it takes to reference any</span>
<span class="doccomment">/// location in memory. For example, on a 32 bit target, this is 4 bytes</span>
<span class="doccomment">/// and on a 64 bit target, this is 8 bytes.</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_isize</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;usize&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// The pointer-sized unsigned integer type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *[See also the `std::usize` module](usize/index.html).*</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The size of this primitive is how many bytes it takes to reference any</span>
<span class="doccomment">/// location in memory. For example, on a 32 bit target, this is 4 bytes</span>
<span class="doccomment">/// and on a 64 bit target, this is 8 bytes.</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_usize</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;reference&quot;</span>)]</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">alias</span> <span class="op">=</span> <span class="string">&quot;&amp;&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// References, both shared and mutable.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// A reference represents a borrow of some owned value. You can get one by using the `&amp;` or `&amp;mut`</span>
<span class="doccomment">/// operators on a value, or by using a `ref` or `ref mut` pattern.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// For those familiar with pointers, a reference is just a pointer that is assumed to not be null.</span>
<span class="doccomment">/// In fact, `Option&lt;&amp;T&gt;` has the same memory representation as a nullable pointer, and can be</span>
<span class="doccomment">/// passed across FFI boundaries as such.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// In most cases, references can be used much like the original value. Field access, method</span>
<span class="doccomment">/// calling, and indexing work the same (save for mutability rules, of course). In addition, the</span>
<span class="doccomment">/// comparison operators transparently defer to the referent&#39;s implementation, allowing references</span>
<span class="doccomment">/// to be compared the same as owned values.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// References have a lifetime attached to them, which represents the scope for which the borrow is</span>
<span class="doccomment">/// valid. A lifetime is said to &quot;outlive&quot; another one if its representative scope is as long or</span>
<span class="doccomment">/// longer than the other. The `&#39;static` lifetime is the longest lifetime, which represents the</span>
<span class="doccomment">/// total life of the program. For example, string literals have a `&#39;static` lifetime because the</span>
<span class="doccomment">/// text data is embedded into the binary of the program, rather than in an allocation that needs</span>
<span class="doccomment">/// to be dynamically managed.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// `&amp;mut T` references can be freely coerced into `&amp;T` references with the same referent type, and</span>
<span class="doccomment">/// references with longer lifetimes can be freely coerced into references with shorter ones.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// For more information on how to use references, see [the book&#39;s section on &quot;References and</span>
<span class="doccomment">/// Borrowing&quot;][book-refs].</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [book-refs]: ../book/second-edition/ch04-02-references-and-borrowing.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The following traits are implemented for all `&amp;T`, regardless of the type of its referent:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// * [`Copy`]</span>
<span class="doccomment">/// * [`Clone`] \(Note that this will not defer to `T`&#39;s `Clone` implementation if it exists!)</span>
<span class="doccomment">/// * [`Deref`]</span>
<span class="doccomment">/// * [`Borrow`]</span>
<span class="doccomment">/// * [`Pointer`]</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`Copy`]: marker/trait.Copy.html</span>
<span class="doccomment">/// [`Clone`]: clone/trait.Clone.html</span>
<span class="doccomment">/// [`Deref`]: ops/trait.Deref.html</span>
<span class="doccomment">/// [`Borrow`]: borrow/trait.Borrow.html</span>
<span class="doccomment">/// [`Pointer`]: fmt/trait.Pointer.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// `&amp;mut T` references get all of the above except `Copy` and `Clone` (to prevent creating</span>
<span class="doccomment">/// multiple simultaneous mutable borrows), plus the following, regardless of the type of its</span>
<span class="doccomment">/// referent:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// * [`DerefMut`]</span>
<span class="doccomment">/// * [`BorrowMut`]</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`DerefMut`]: ops/trait.DerefMut.html</span>
<span class="doccomment">/// [`BorrowMut`]: borrow/trait.BorrowMut.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The following traits are implemented on `&amp;T` references if the underlying `T` also implements</span>
<span class="doccomment">/// that trait:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// * All the traits in [`std::fmt`] except [`Pointer`] and [`fmt::Write`]</span>
<span class="doccomment">/// * [`PartialOrd`]</span>
<span class="doccomment">/// * [`Ord`]</span>
<span class="doccomment">/// * [`PartialEq`]</span>
<span class="doccomment">/// * [`Eq`]</span>
<span class="doccomment">/// * [`AsRef`]</span>
<span class="doccomment">/// * [`Fn`] \(in addition, `&amp;T` references get [`FnMut`] and [`FnOnce`] if `T: Fn`)</span>
<span class="doccomment">/// * [`Hash`]</span>
<span class="doccomment">/// * [`ToSocketAddrs`]</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`std::fmt`]: fmt/index.html</span>
<span class="doccomment">/// [`fmt::Write`]: fmt/trait.Write.html</span>
<span class="doccomment">/// [`PartialOrd`]: cmp/trait.PartialOrd.html</span>
<span class="doccomment">/// [`Ord`]: cmp/trait.Ord.html</span>
<span class="doccomment">/// [`PartialEq`]: cmp/trait.PartialEq.html</span>
<span class="doccomment">/// [`Eq`]: cmp/trait.Eq.html</span>
<span class="doccomment">/// [`AsRef`]: convert/trait.AsRef.html</span>
<span class="doccomment">/// [`Fn`]: ops/trait.Fn.html</span>
<span class="doccomment">/// [`FnMut`]: ops/trait.FnMut.html</span>
<span class="doccomment">/// [`FnOnce`]: ops/trait.FnOnce.html</span>
<span class="doccomment">/// [`Hash`]: hash/trait.Hash.html</span>
<span class="doccomment">/// [`ToSocketAddrs`]: net/trait.ToSocketAddrs.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// `&amp;mut T` references get all of the above except `ToSocketAddrs`, plus the following, if `T`</span>
<span class="doccomment">/// implements that trait:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// * [`AsMut`]</span>
<span class="doccomment">/// * [`FnMut`] \(in addition, `&amp;mut T` references get [`FnOnce`] if `T: FnMut`)</span>
<span class="doccomment">/// * [`fmt::Write`]</span>
<span class="doccomment">/// * [`Iterator`]</span>
<span class="doccomment">/// * [`DoubleEndedIterator`]</span>
<span class="doccomment">/// * [`ExactSizeIterator`]</span>
<span class="doccomment">/// * [`FusedIterator`]</span>
<span class="doccomment">/// * [`TrustedLen`]</span>
<span class="doccomment">/// * [`Send`] \(note that `&amp;T` references only get `Send` if `T: Sync`)</span>
<span class="doccomment">/// * [`io::Write`]</span>
<span class="doccomment">/// * [`Read`]</span>
<span class="doccomment">/// * [`Seek`]</span>
<span class="doccomment">/// * [`BufRead`]</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`AsMut`]: convert/trait.AsMut.html</span>
<span class="doccomment">/// [`Iterator`]: iter/trait.Iterator.html</span>
<span class="doccomment">/// [`DoubleEndedIterator`]: iter/trait.DoubleEndedIterator.html</span>
<span class="doccomment">/// [`ExactSizeIterator`]: iter/trait.ExactSizeIterator.html</span>
<span class="doccomment">/// [`FusedIterator`]: iter/trait.FusedIterator.html</span>
<span class="doccomment">/// [`TrustedLen`]: iter/trait.TrustedLen.html</span>
<span class="doccomment">/// [`Send`]: marker/trait.Send.html</span>
<span class="doccomment">/// [`io::Write`]: io/trait.Write.html</span>
<span class="doccomment">/// [`Read`]: io/trait.Read.html</span>
<span class="doccomment">/// [`Seek`]: io/trait.Seek.html</span>
<span class="doccomment">/// [`BufRead`]: io/trait.BufRead.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Note that due to method call deref coercion, simply calling a trait method will act like they</span>
<span class="doccomment">/// work on references as well as they do on owned values! The implementations described here are</span>
<span class="doccomment">/// meant for generic contexts, where the final type `T` is a type parameter or otherwise not</span>
<span class="doccomment">/// locally known.</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_ref</span> { }

<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">primitive</span> <span class="op">=</span> <span class="string">&quot;fn&quot;</span>)]</span>
<span class="comment">//</span>
<span class="doccomment">/// Function pointers, like `fn(usize) -&gt; bool`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// *See also the traits [`Fn`], [`FnMut`], and [`FnOnce`].*</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`Fn`]: ops/trait.Fn.html</span>
<span class="doccomment">/// [`FnMut`]: ops/trait.FnMut.html</span>
<span class="doccomment">/// [`FnOnce`]: ops/trait.FnOnce.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Plain function pointers are obtained by casting either plain functions, or closures that don&#39;t</span>
<span class="doccomment">/// capture an environment:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// fn add_one(x: usize) -&gt; usize {</span>
<span class="doccomment">///     x + 1</span>
<span class="doccomment">/// }</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let ptr: fn(usize) -&gt; usize = add_one;</span>
<span class="doccomment">/// assert_eq!(ptr(5), 6);</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let clos: fn(usize) -&gt; usize = |x| x + 5;</span>
<span class="doccomment">/// assert_eq!(clos(5), 10);</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// In addition to varying based on their signature, function pointers come in two flavors: safe</span>
<span class="doccomment">/// and unsafe. Plain `fn()` function pointers can only point to safe functions,</span>
<span class="doccomment">/// while `unsafe fn()` function pointers can point to safe or unsafe functions.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// fn add_one(x: usize) -&gt; usize {</span>
<span class="doccomment">///     x + 1</span>
<span class="doccomment">/// }</span>
<span class="doccomment">///</span>
<span class="doccomment">/// unsafe fn add_one_unsafely(x: usize) -&gt; usize {</span>
<span class="doccomment">///     x + 1</span>
<span class="doccomment">/// }</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let safe_ptr: fn(usize) -&gt; usize = add_one;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// //ERROR: mismatched types: expected normal fn, found unsafe fn</span>
<span class="doccomment">/// //let bad_ptr: fn(usize) -&gt; usize = add_one_unsafely;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let unsafe_ptr: unsafe fn(usize) -&gt; usize = add_one_unsafely;</span>
<span class="doccomment">/// let really_safe_ptr: unsafe fn(usize) -&gt; usize = add_one;</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// On top of that, function pointers can vary based on what ABI they use. This is achieved by</span>
<span class="doccomment">/// adding the `extern` keyword to the type name, followed by the ABI in question. For example,</span>
<span class="doccomment">/// `fn()` is different from `extern &quot;C&quot; fn()`, which itself is different from `extern &quot;stdcall&quot;</span>
<span class="doccomment">/// fn()`, and so on for the various ABIs that Rust supports.  Non-`extern` functions have an ABI</span>
<span class="doccomment">/// of `&quot;Rust&quot;`, and `extern` functions without an explicit ABI have an ABI of `&quot;C&quot;`. For more</span>
<span class="doccomment">/// information, see [the nomicon&#39;s section on foreign calling conventions][nomicon-abi].</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [nomicon-abi]: ../nomicon/ffi.html#foreign-calling-conventions</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Extern function declarations with the &quot;C&quot; or &quot;cdecl&quot; ABIs can also be *variadic*, allowing them</span>
<span class="doccomment">/// to be called with a variable number of arguments. Normal rust functions, even those with an</span>
<span class="doccomment">/// `extern &quot;ABI&quot;`, cannot be variadic. For more information, see [the nomicon&#39;s section on</span>
<span class="doccomment">/// variadic functions][nomicon-variadic].</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [nomicon-variadic]: ../nomicon/ffi.html#variadic-functions</span>
<span class="doccomment">///</span>
<span class="doccomment">/// These markers can be combined, so `unsafe extern &quot;stdcall&quot; fn()` is a valid type.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Like references in rust, function pointers are assumed to not be null, so if you want to pass a</span>
<span class="doccomment">/// function pointer over FFI and be able to accommodate null pointers, make your type</span>
<span class="doccomment">/// `Option&lt;fn()&gt;` with your required signature.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Function pointers implement the following traits:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// * [`Clone`]</span>
<span class="doccomment">/// * [`PartialEq`]</span>
<span class="doccomment">/// * [`Eq`]</span>
<span class="doccomment">/// * [`PartialOrd`]</span>
<span class="doccomment">/// * [`Ord`]</span>
<span class="doccomment">/// * [`Hash`]</span>
<span class="doccomment">/// * [`Pointer`]</span>
<span class="doccomment">/// * [`Debug`]</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`Clone`]: clone/trait.Clone.html</span>
<span class="doccomment">/// [`PartialEq`]: cmp/trait.PartialEq.html</span>
<span class="doccomment">/// [`Eq`]: cmp/trait.Eq.html</span>
<span class="doccomment">/// [`PartialOrd`]: cmp/trait.PartialOrd.html</span>
<span class="doccomment">/// [`Ord`]: cmp/trait.Ord.html</span>
<span class="doccomment">/// [`Hash`]: hash/trait.Hash.html</span>
<span class="doccomment">/// [`Pointer`]: fmt/trait.Pointer.html</span>
<span class="doccomment">/// [`Debug`]: fmt/trait.Debug.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Due to a temporary restriction in Rust&#39;s type system, these traits are only implemented on</span>
<span class="doccomment">/// functions that take 12 arguments or less, with the `&quot;Rust&quot;` and `&quot;C&quot;` ABIs. In the future, this</span>
<span class="doccomment">/// may change.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// In addition, function pointers of *any* signature, ABI, or safety are [`Copy`], and all *safe*</span>
<span class="doccomment">/// function pointers implement [`Fn`], [`FnMut`], and [`FnOnce`]. This works because these traits</span>
<span class="doccomment">/// are specially known to the compiler.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`Copy`]: marker/trait.Copy.html</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">&quot;rust1&quot;</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">&quot;1.0.0&quot;</span>)]</span>
<span class="kw">mod</span> <span class="ident">prim_fn</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><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 = "std";</script><script src="../../aliases.js"></script><script src="../../main.js"></script><script defer src="../../search-index.js"></script></body></html>