<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta name="generator" content="rustdoc">
<meta name="description" content="Source to the Rust file `/home/jule/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.1.80/src/lib.rs`.">
<meta name="keywords" content="rust, rustlang, rust-lang">
<title>lib.rs.html -- source</title>
<link rel="stylesheet" type="text/css" href="../../normalize.css">
<link rel="stylesheet" type="text/css" href="../../rustdoc.css">
<link rel="stylesheet" type="text/css" href="../../main.css">
<link rel="shortcut icon" href="https://www.rust-lang.org/favicon.ico">
</head>
<body class="rustdoc source">
<!--[if lte IE 8]>
<div class="warning">
This old browser is unsupported and will most likely display funky
things.
</div>
<![endif]-->
<nav class="sidebar">
<a href='../../regex/index.html'><img src='https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png' alt='logo' width='100'></a>
</nav>
<nav class="sub">
<form class="search-form js-only">
<div class="search-container">
<input class="search-input" name="search"
autocomplete="off"
placeholder="Click or press ‘S’ to search, ‘?’ for more options…"
type="search">
</div>
</form>
</nav>
<section id='main' class="content"><pre class="line-numbers"><span id="1"> 1</span>
<span id="2"> 2</span>
<span id="3"> 3</span>
<span id="4"> 4</span>
<span id="5"> 5</span>
<span id="6"> 6</span>
<span id="7"> 7</span>
<span id="8"> 8</span>
<span id="9"> 9</span>
<span id="10"> 10</span>
<span id="11"> 11</span>
<span id="12"> 12</span>
<span id="13"> 13</span>
<span id="14"> 14</span>
<span id="15"> 15</span>
<span id="16"> 16</span>
<span id="17"> 17</span>
<span id="18"> 18</span>
<span id="19"> 19</span>
<span id="20"> 20</span>
<span id="21"> 21</span>
<span id="22"> 22</span>
<span id="23"> 23</span>
<span id="24"> 24</span>
<span id="25"> 25</span>
<span id="26"> 26</span>
<span id="27"> 27</span>
<span id="28"> 28</span>
<span id="29"> 29</span>
<span id="30"> 30</span>
<span id="31"> 31</span>
<span id="32"> 32</span>
<span id="33"> 33</span>
<span id="34"> 34</span>
<span id="35"> 35</span>
<span id="36"> 36</span>
<span id="37"> 37</span>
<span id="38"> 38</span>
<span id="39"> 39</span>
<span id="40"> 40</span>
<span id="41"> 41</span>
<span id="42"> 42</span>
<span id="43"> 43</span>
<span id="44"> 44</span>
<span id="45"> 45</span>
<span id="46"> 46</span>
<span id="47"> 47</span>
<span id="48"> 48</span>
<span id="49"> 49</span>
<span id="50"> 50</span>
<span id="51"> 51</span>
<span id="52"> 52</span>
<span id="53"> 53</span>
<span id="54"> 54</span>
<span id="55"> 55</span>
<span id="56"> 56</span>
<span id="57"> 57</span>
<span id="58"> 58</span>
<span id="59"> 59</span>
<span id="60"> 60</span>
<span id="61"> 61</span>
<span id="62"> 62</span>
<span id="63"> 63</span>
<span id="64"> 64</span>
<span id="65"> 65</span>
<span id="66"> 66</span>
<span id="67"> 67</span>
<span id="68"> 68</span>
<span id="69"> 69</span>
<span id="70"> 70</span>
<span id="71"> 71</span>
<span id="72"> 72</span>
<span id="73"> 73</span>
<span id="74"> 74</span>
<span id="75"> 75</span>
<span id="76"> 76</span>
<span id="77"> 77</span>
<span id="78"> 78</span>
<span id="79"> 79</span>
<span id="80"> 80</span>
<span id="81"> 81</span>
<span id="82"> 82</span>
<span id="83"> 83</span>
<span id="84"> 84</span>
<span id="85"> 85</span>
<span id="86"> 86</span>
<span id="87"> 87</span>
<span id="88"> 88</span>
<span id="89"> 89</span>
<span id="90"> 90</span>
<span id="91"> 91</span>
<span id="92"> 92</span>
<span id="93"> 93</span>
<span id="94"> 94</span>
<span id="95"> 95</span>
<span id="96"> 96</span>
<span id="97"> 97</span>
<span id="98"> 98</span>
<span id="99"> 99</span>
<span id="100">100</span>
<span id="101">101</span>
<span id="102">102</span>
<span id="103">103</span>
<span id="104">104</span>
<span id="105">105</span>
<span id="106">106</span>
<span id="107">107</span>
<span id="108">108</span>
<span id="109">109</span>
<span id="110">110</span>
<span id="111">111</span>
<span id="112">112</span>
<span id="113">113</span>
<span id="114">114</span>
<span id="115">115</span>
<span id="116">116</span>
<span id="117">117</span>
<span id="118">118</span>
<span id="119">119</span>
<span id="120">120</span>
<span id="121">121</span>
<span id="122">122</span>
<span id="123">123</span>
<span id="124">124</span>
<span id="125">125</span>
<span id="126">126</span>
<span id="127">127</span>
<span id="128">128</span>
<span id="129">129</span>
<span id="130">130</span>
<span id="131">131</span>
<span id="132">132</span>
<span id="133">133</span>
<span id="134">134</span>
<span id="135">135</span>
<span id="136">136</span>
<span id="137">137</span>
<span id="138">138</span>
<span id="139">139</span>
<span id="140">140</span>
<span id="141">141</span>
<span id="142">142</span>
<span id="143">143</span>
<span id="144">144</span>
<span id="145">145</span>
<span id="146">146</span>
<span id="147">147</span>
<span id="148">148</span>
<span id="149">149</span>
<span id="150">150</span>
<span id="151">151</span>
<span id="152">152</span>
<span id="153">153</span>
<span id="154">154</span>
<span id="155">155</span>
<span id="156">156</span>
<span id="157">157</span>
<span id="158">158</span>
<span id="159">159</span>
<span id="160">160</span>
<span id="161">161</span>
<span id="162">162</span>
<span id="163">163</span>
<span id="164">164</span>
<span id="165">165</span>
<span id="166">166</span>
<span id="167">167</span>
<span id="168">168</span>
<span id="169">169</span>
<span id="170">170</span>
<span id="171">171</span>
<span id="172">172</span>
<span id="173">173</span>
<span id="174">174</span>
<span id="175">175</span>
<span id="176">176</span>
<span id="177">177</span>
<span id="178">178</span>
<span id="179">179</span>
<span id="180">180</span>
<span id="181">181</span>
<span id="182">182</span>
<span id="183">183</span>
<span id="184">184</span>
<span id="185">185</span>
<span id="186">186</span>
<span id="187">187</span>
<span id="188">188</span>
<span id="189">189</span>
<span id="190">190</span>
<span id="191">191</span>
<span id="192">192</span>
<span id="193">193</span>
<span id="194">194</span>
<span id="195">195</span>
<span id="196">196</span>
<span id="197">197</span>
<span id="198">198</span>
<span id="199">199</span>
<span id="200">200</span>
<span id="201">201</span>
<span id="202">202</span>
<span id="203">203</span>
<span id="204">204</span>
<span id="205">205</span>
<span id="206">206</span>
<span id="207">207</span>
<span id="208">208</span>
<span id="209">209</span>
<span id="210">210</span>
<span id="211">211</span>
<span id="212">212</span>
<span id="213">213</span>
<span id="214">214</span>
<span id="215">215</span>
<span id="216">216</span>
<span id="217">217</span>
<span id="218">218</span>
<span id="219">219</span>
<span id="220">220</span>
<span id="221">221</span>
<span id="222">222</span>
<span id="223">223</span>
<span id="224">224</span>
<span id="225">225</span>
<span id="226">226</span>
<span id="227">227</span>
<span id="228">228</span>
<span id="229">229</span>
<span id="230">230</span>
<span id="231">231</span>
<span id="232">232</span>
<span id="233">233</span>
<span id="234">234</span>
<span id="235">235</span>
<span id="236">236</span>
<span id="237">237</span>
<span id="238">238</span>
<span id="239">239</span>
<span id="240">240</span>
<span id="241">241</span>
<span id="242">242</span>
<span id="243">243</span>
<span id="244">244</span>
<span id="245">245</span>
<span id="246">246</span>
<span id="247">247</span>
<span id="248">248</span>
<span id="249">249</span>
<span id="250">250</span>
<span id="251">251</span>
<span id="252">252</span>
<span id="253">253</span>
<span id="254">254</span>
<span id="255">255</span>
<span id="256">256</span>
<span id="257">257</span>
<span id="258">258</span>
<span id="259">259</span>
<span id="260">260</span>
<span id="261">261</span>
<span id="262">262</span>
<span id="263">263</span>
<span id="264">264</span>
<span id="265">265</span>
<span id="266">266</span>
<span id="267">267</span>
<span id="268">268</span>
<span id="269">269</span>
<span id="270">270</span>
<span id="271">271</span>
<span id="272">272</span>
<span id="273">273</span>
<span id="274">274</span>
<span id="275">275</span>
<span id="276">276</span>
<span id="277">277</span>
<span id="278">278</span>
<span id="279">279</span>
<span id="280">280</span>
<span id="281">281</span>
<span id="282">282</span>
<span id="283">283</span>
<span id="284">284</span>
<span id="285">285</span>
<span id="286">286</span>
<span id="287">287</span>
<span id="288">288</span>
<span id="289">289</span>
<span id="290">290</span>
<span id="291">291</span>
<span id="292">292</span>
<span id="293">293</span>
<span id="294">294</span>
<span id="295">295</span>
<span id="296">296</span>
<span id="297">297</span>
<span id="298">298</span>
<span id="299">299</span>
<span id="300">300</span>
<span id="301">301</span>
<span id="302">302</span>
<span id="303">303</span>
<span id="304">304</span>
<span id="305">305</span>
<span id="306">306</span>
<span id="307">307</span>
<span id="308">308</span>
<span id="309">309</span>
<span id="310">310</span>
<span id="311">311</span>
<span id="312">312</span>
<span id="313">313</span>
<span id="314">314</span>
<span id="315">315</span>
<span id="316">316</span>
<span id="317">317</span>
<span id="318">318</span>
<span id="319">319</span>
<span id="320">320</span>
<span id="321">321</span>
<span id="322">322</span>
<span id="323">323</span>
<span id="324">324</span>
<span id="325">325</span>
<span id="326">326</span>
<span id="327">327</span>
<span id="328">328</span>
<span id="329">329</span>
<span id="330">330</span>
<span id="331">331</span>
<span id="332">332</span>
<span id="333">333</span>
<span id="334">334</span>
<span id="335">335</span>
<span id="336">336</span>
<span id="337">337</span>
<span id="338">338</span>
<span id="339">339</span>
<span id="340">340</span>
<span id="341">341</span>
<span id="342">342</span>
<span id="343">343</span>
<span id="344">344</span>
<span id="345">345</span>
<span id="346">346</span>
<span id="347">347</span>
<span id="348">348</span>
<span id="349">349</span>
<span id="350">350</span>
<span id="351">351</span>
<span id="352">352</span>
<span id="353">353</span>
<span id="354">354</span>
<span id="355">355</span>
<span id="356">356</span>
<span id="357">357</span>
<span id="358">358</span>
<span id="359">359</span>
<span id="360">360</span>
<span id="361">361</span>
<span id="362">362</span>
<span id="363">363</span>
<span id="364">364</span>
<span id="365">365</span>
<span id="366">366</span>
<span id="367">367</span>
<span id="368">368</span>
<span id="369">369</span>
<span id="370">370</span>
<span id="371">371</span>
<span id="372">372</span>
<span id="373">373</span>
<span id="374">374</span>
<span id="375">375</span>
<span id="376">376</span>
<span id="377">377</span>
<span id="378">378</span>
<span id="379">379</span>
<span id="380">380</span>
<span id="381">381</span>
<span id="382">382</span>
<span id="383">383</span>
<span id="384">384</span>
<span id="385">385</span>
<span id="386">386</span>
<span id="387">387</span>
<span id="388">388</span>
<span id="389">389</span>
<span id="390">390</span>
<span id="391">391</span>
<span id="392">392</span>
<span id="393">393</span>
<span id="394">394</span>
<span id="395">395</span>
<span id="396">396</span>
<span id="397">397</span>
<span id="398">398</span>
<span id="399">399</span>
<span id="400">400</span>
<span id="401">401</span>
<span id="402">402</span>
<span id="403">403</span>
<span id="404">404</span>
<span id="405">405</span>
<span id="406">406</span>
<span id="407">407</span>
<span id="408">408</span>
<span id="409">409</span>
<span id="410">410</span>
<span id="411">411</span>
<span id="412">412</span>
<span id="413">413</span>
<span id="414">414</span>
<span id="415">415</span>
<span id="416">416</span>
<span id="417">417</span>
<span id="418">418</span>
<span id="419">419</span>
<span id="420">420</span>
<span id="421">421</span>
<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>
</pre><pre class="rust ">
<span class="comment">// Copyright 2014-2015 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 <LICENSE-APACHE or</span>
<span class="comment">// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license</span>
<span class="comment">// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your</span>
<span class="comment">// option. This file may not be copied, modified, or distributed</span>
<span class="comment">// except according to those terms.</span>
<span class="doccomment">//! This crate provides a native implementation of regular expressions that is</span>
<span class="doccomment">//! heavily based on RE2 both in syntax and in implementation. Notably,</span>
<span class="doccomment">//! backreferences and arbitrary lookahead/lookbehind assertions are not</span>
<span class="doccomment">//! provided. In return, regular expression searching provided by this package</span>
<span class="doccomment">//! has excellent worst-case performance. The specific syntax supported is</span>
<span class="doccomment">//! documented further down.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! This crate's documentation provides some simple examples, describes Unicode</span>
<span class="doccomment">//! support and exhaustively lists the supported syntax. For more specific</span>
<span class="doccomment">//! details on the API, please see the documentation for the</span>
<span class="doccomment">//! [`Regex`](struct.Regex.html) type.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Usage</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! This crate is [on crates.io](https://crates.io/crates/regex) and can be</span>
<span class="doccomment">//! used by adding `regex` to your dependencies in your project's `Cargo.toml`.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```toml</span>
<span class="doccomment">//! [dependencies]</span>
<span class="doccomment">//! regex = "0.1"</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! and this to your crate root:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! extern crate regex;</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Example: find a date</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! General use of regular expressions in this package involves compiling an</span>
<span class="doccomment">//! expression and then using it to search, split or replace text. For example,</span>
<span class="doccomment">//! to confirm that some text resembles a date:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! use regex::Regex;</span>
<span class="doccomment">//! let re = Regex::new(r"^\d{4}-\d{2}-\d{2}$").unwrap();</span>
<span class="doccomment">//! assert!(re.is_match("2014-01-01"));</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Notice the use of the `^` and `$` anchors. In this crate, every expression</span>
<span class="doccomment">//! is executed with an implicit `.*?` at the beginning and end, which allows</span>
<span class="doccomment">//! it to match anywhere in the text. Anchors can be used to ensure that the</span>
<span class="doccomment">//! full text matches an expression.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! This example also demonstrates the utility of</span>
<span class="doccomment">//! [raw strings](https://doc.rust-lang.org/stable/reference.html#raw-string-literals)</span>
<span class="doccomment">//! in Rust, which</span>
<span class="doccomment">//! are just like regular strings except they are prefixed with an `r` and do</span>
<span class="doccomment">//! not process any escape sequences. For example, `"\\d"` is the same</span>
<span class="doccomment">//! expression as `r"\d"`.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Example: Avoid compiling the same regex in a loop</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! It is an anti-pattern to compile the same regular expression in a loop</span>
<span class="doccomment">//! since compilation is typically expensive. (It takes anywhere from a few</span>
<span class="doccomment">//! microseconds to a few **milliseconds** depending on the size of the</span>
<span class="doccomment">//! regex.) Not only is compilation itself expensive, but this also prevents</span>
<span class="doccomment">//! optimizations that reuse allocations internally to the matching engines.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! In Rust, it can sometimes be a pain to pass regular expressions around if</span>
<span class="doccomment">//! they're used from inside a helper function. Instead, we recommend using the</span>
<span class="doccomment">//! [`lazy_static`](https://crates.io/crates/lazy_static) crate to ensure that</span>
<span class="doccomment">//! regular expressions are compiled exactly once.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! For example:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! #[macro_use] extern crate lazy_static;</span>
<span class="doccomment">//! extern crate regex;</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! use regex::Regex;</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! fn some_helper_function(text: &str) -> bool {</span>
<span class="doccomment">//! lazy_static! {</span>
<span class="doccomment">//! static ref RE: Regex = Regex::new("...").unwrap();</span>
<span class="doccomment">//! }</span>
<span class="doccomment">//! RE.is_match(text)</span>
<span class="doccomment">//! }</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! fn main() {}</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Specifically, in this example, the regex will be compiled when it is used for</span>
<span class="doccomment">//! the first time. On subsequent uses, it will reuse the previous compilation.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Example: iterating over capture groups</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! This crate provides convenient iterators for matching an expression</span>
<span class="doccomment">//! repeatedly against a search string to find successive non-overlapping</span>
<span class="doccomment">//! matches. For example, to find all dates in a string and be able to access</span>
<span class="doccomment">//! them by their component pieces:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! # extern crate regex; use regex::Regex;</span>
<span class="doccomment">//! # fn main() {</span>
<span class="doccomment">//! let re = Regex::new(r"(\d{4})-(\d{2})-(\d{2})").unwrap();</span>
<span class="doccomment">//! let text = "2012-03-14, 2013-01-01 and 2014-07-05";</span>
<span class="doccomment">//! for cap in re.captures_iter(text) {</span>
<span class="doccomment">//! println!("Month: {} Day: {} Year: {}",</span>
<span class="doccomment">//! cap.at(2).unwrap_or(""), cap.at(3).unwrap_or(""),</span>
<span class="doccomment">//! cap.at(1).unwrap_or(""));</span>
<span class="doccomment">//! }</span>
<span class="doccomment">//! // Output:</span>
<span class="doccomment">//! // Month: 03 Day: 14 Year: 2012</span>
<span class="doccomment">//! // Month: 01 Day: 01 Year: 2013</span>
<span class="doccomment">//! // Month: 07 Day: 05 Year: 2014</span>
<span class="doccomment">//! # }</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Notice that the year is in the capture group indexed at `1`. This is</span>
<span class="doccomment">//! because the *entire match* is stored in the capture group at index `0`.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Example: replacement with named capture groups</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Building on the previous example, perhaps we'd like to rearrange the date</span>
<span class="doccomment">//! formats. This can be done with text replacement. But to make the code</span>
<span class="doccomment">//! clearer, we can *name* our capture groups and use those names as variables</span>
<span class="doccomment">//! in our replacement text:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! # extern crate regex; use regex::Regex;</span>
<span class="doccomment">//! # fn main() {</span>
<span class="doccomment">//! let re = Regex::new(r"(?P<y>\d{4})-(?P<m>\d{2})-(?P<d>\d{2})").unwrap();</span>
<span class="doccomment">//! let before = "2012-03-14, 2013-01-01 and 2014-07-05";</span>
<span class="doccomment">//! let after = re.replace_all(before, "$m/$d/$y");</span>
<span class="doccomment">//! assert_eq!(after, "03/14/2012, 01/01/2013 and 07/05/2014");</span>
<span class="doccomment">//! # }</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! The `replace` methods are actually polymorphic in the replacement, which</span>
<span class="doccomment">//! provides more flexibility than is seen here. (See the documentation for</span>
<span class="doccomment">//! `Regex::replace` for more details.)</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Note that if your regex gets complicated, you can use the `x` flag to</span>
<span class="doccomment">//! enable insigificant whitespace mode, which also lets you write comments:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! # extern crate regex; use regex::Regex;</span>
<span class="doccomment">//! # fn main() {</span>
<span class="doccomment">//! let re = Regex::new(r"(?x)</span>
<span class="doccomment">//! (?P<y>\d{4}) # the year</span>
<span class="doccomment">//! -</span>
<span class="doccomment">//! (?P<m>\d{2}) # the month</span>
<span class="doccomment">//! -</span>
<span class="doccomment">//! (?P<d>\d{2}) # the day</span>
<span class="doccomment">//! ").unwrap();</span>
<span class="doccomment">//! let before = "2012-03-14, 2013-01-01 and 2014-07-05";</span>
<span class="doccomment">//! let after = re.replace_all(before, "$m/$d/$y");</span>
<span class="doccomment">//! assert_eq!(after, "03/14/2012, 01/01/2013 and 07/05/2014");</span>
<span class="doccomment">//! # }</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Example: match multiple regular expressions simultaneously</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! This demonstrates how to use a `RegexSet` to match multiple (possibly</span>
<span class="doccomment">//! overlapping) regular expressions in a single scan of the search text:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! use regex::RegexSet;</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! let set = RegexSet::new(&[</span>
<span class="doccomment">//! r"\w+",</span>
<span class="doccomment">//! r"\d+",</span>
<span class="doccomment">//! r"\pL+",</span>
<span class="doccomment">//! r"foo",</span>
<span class="doccomment">//! r"bar",</span>
<span class="doccomment">//! r"barfoo",</span>
<span class="doccomment">//! r"foobar",</span>
<span class="doccomment">//! ]).unwrap();</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! // Iterate over and collect all of the matches.</span>
<span class="doccomment">//! let matches: Vec<_> = set.matches("foobar").into_iter().collect();</span>
<span class="doccomment">//! assert_eq!(matches, vec![0, 2, 3, 4, 6]);</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! // You can also test whether a particular regex matched:</span>
<span class="doccomment">//! let matches = set.matches("foobar");</span>
<span class="doccomment">//! assert!(!matches.matched(5));</span>
<span class="doccomment">//! assert!(matches.matched(6));</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Pay for what you use</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! With respect to searching text with a regular expression, there are three</span>
<span class="doccomment">//! questions that can be asked:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! 1. Does the text match this expression?</span>
<span class="doccomment">//! 2. If so, where does it match?</span>
<span class="doccomment">//! 3. Where are the submatches?</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Generally speaking, this crate could provide a function to answer only #3,</span>
<span class="doccomment">//! which would subsume #1 and #2 automatically. However, it can be</span>
<span class="doccomment">//! significantly more expensive to compute the location of submatches, so it's</span>
<span class="doccomment">//! best not to do it if you don't need to.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Therefore, only use what you need. For example, don't use `find` if you</span>
<span class="doccomment">//! only need to test if an expression matches a string. (Use `is_match`</span>
<span class="doccomment">//! instead.)</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Unicode</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! This implementation executes regular expressions **only** on valid UTF-8</span>
<span class="doccomment">//! while exposing match locations as byte indices into the search string.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Only simple case folding is supported. Namely, when matching</span>
<span class="doccomment">//! case-insensitively, the characters are first mapped using the [simple case</span>
<span class="doccomment">//! folding](ftp://ftp.unicode.org/Public/UNIDATA/CaseFolding.txt) mapping</span>
<span class="doccomment">//! before matching.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Regular expressions themselves are **only** interpreted as a sequence of</span>
<span class="doccomment">//! Unicode scalar values. This means you can use Unicode characters directly</span>
<span class="doccomment">//! in your expression:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! # extern crate regex; use regex::Regex;</span>
<span class="doccomment">//! # fn main() {</span>
<span class="doccomment">//! let re = Regex::new(r"(?i)Δ+").unwrap();</span>
<span class="doccomment">//! assert_eq!(re.find("ΔδΔ"), Some((0, 6)));</span>
<span class="doccomment">//! # }</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Finally, Unicode general categories and scripts are available as character</span>
<span class="doccomment">//! classes. For example, you can match a sequence of numerals, Greek or</span>
<span class="doccomment">//! Cherokee letters:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! # extern crate regex; use regex::Regex;</span>
<span class="doccomment">//! # fn main() {</span>
<span class="doccomment">//! let re = Regex::new(r"[\pN\p{Greek}\p{Cherokee}]+").unwrap();</span>
<span class="doccomment">//! assert_eq!(re.find("abcΔᎠβⅠᏴγδⅡxyz"), Some((3, 23)));</span>
<span class="doccomment">//! # }</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Opt out of Unicode support</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! The `bytes` sub-module provides a `Regex` type that can be used to match</span>
<span class="doccomment">//! on `&[u8]`. By default, text is interpreted as ASCII compatible text with</span>
<span class="doccomment">//! all Unicode support disabled (e.g., `.` matches any byte instead of any</span>
<span class="doccomment">//! Unicode codepoint). Unicode support can be selectively enabled with the</span>
<span class="doccomment">//! `u` flag. See the `bytes` module documentation for more details.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Unicode support can also be selectively *disabled* with the main `Regex`</span>
<span class="doccomment">//! type that matches on `&str`. For example, `(?-u:\b)` will match an ASCII</span>
<span class="doccomment">//! word boundary. Note though that invalid UTF-8 is not allowed to be matched</span>
<span class="doccomment">//! even when the `u` flag is disabled. For example, `(?-u:.)` will return an</span>
<span class="doccomment">//! error, since `.` matches *any byte* when Unicode support is disabled.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Syntax</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! The syntax supported in this crate is almost in an exact correspondence</span>
<span class="doccomment">//! with the syntax supported by RE2. It is documented below.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Note that the regular expression parser and abstract syntax are exposed in</span>
<span class="doccomment">//! a separate crate, [`regex-syntax`](../regex_syntax/index.html).</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ## Matching one character</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! <pre class="rust"></span>
<span class="doccomment">//! . any character except new line (includes new line with s flag)</span>
<span class="doccomment">//! [xyz] A character class matching either x, y or z.</span>
<span class="doccomment">//! [^xyz] A character class matching any character except x, y and z.</span>
<span class="doccomment">//! [a-z] A character class matching any character in range a-z.</span>
<span class="doccomment">//! \d digit (\p{Nd})</span>
<span class="doccomment">//! \D not digit</span>
<span class="doccomment">//! [:alpha:] ASCII character class ([A-Za-z])</span>
<span class="doccomment">//! [:^alpha:] Negated ASCII character class ([^A-Za-z])</span>
<span class="doccomment">//! \pN One-letter name Unicode character class</span>
<span class="doccomment">//! \p{Greek} Unicode character class (general category or script)</span>
<span class="doccomment">//! \PN Negated one-letter name Unicode character class</span>
<span class="doccomment">//! \P{Greek} negated Unicode character class (general category or script)</span>
<span class="doccomment">//! </pre></span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Any named character class may appear inside a bracketed `[...]` character</span>
<span class="doccomment">//! class. For example, `[\p{Greek}\pN]` matches any Greek or numeral</span>
<span class="doccomment">//! character.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ## Composites</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! <pre class="rust"></span>
<span class="doccomment">//! xy concatenation (x followed by y)</span>
<span class="doccomment">//! x|y alternation (x or y, prefer x)</span>
<span class="doccomment">//! </pre></span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ## Repetitions</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! <pre class="rust"></span>
<span class="doccomment">//! x* zero or more of x (greedy)</span>
<span class="doccomment">//! x+ one or more of x (greedy)</span>
<span class="doccomment">//! x? zero or one of x (greedy)</span>
<span class="doccomment">//! x*? zero or more of x (ungreedy/lazy)</span>
<span class="doccomment">//! x+? one or more of x (ungreedy/lazy)</span>
<span class="doccomment">//! x?? zero or one of x (ungreedy/lazy)</span>
<span class="doccomment">//! x{n,m} at least n x and at most m x (greedy)</span>
<span class="doccomment">//! x{n,} at least n x (greedy)</span>
<span class="doccomment">//! x{n} exactly n x</span>
<span class="doccomment">//! x{n,m}? at least n x and at most m x (ungreedy/lazy)</span>
<span class="doccomment">//! x{n,}? at least n x (ungreedy/lazy)</span>
<span class="doccomment">//! x{n}? exactly n x</span>
<span class="doccomment">//! </pre></span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ## Empty matches</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! <pre class="rust"></span>
<span class="doccomment">//! ^ the beginning of text (or start-of-line with multi-line mode)</span>
<span class="doccomment">//! $ the end of text (or end-of-line with multi-line mode)</span>
<span class="doccomment">//! \A only the beginning of text (even with multi-line mode enabled)</span>
<span class="doccomment">//! \z only the end of text (even with multi-line mode enabled)</span>
<span class="doccomment">//! \b a Unicode word boundary (\w on one side and \W, \A, or \z on other)</span>
<span class="doccomment">//! \B not a Unicode word boundary</span>
<span class="doccomment">//! </pre></span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ## Grouping and flags</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! <pre class="rust"></span>
<span class="doccomment">//! (exp) numbered capture group (indexed by opening parenthesis)</span>
<span class="doccomment">//! (?P&lt;name&gt;exp) named (also numbered) capture group (allowed chars: [_0-9a-zA-Z])</span>
<span class="doccomment">//! (?:exp) non-capturing group</span>
<span class="doccomment">//! (?flags) set flags within current group</span>
<span class="doccomment">//! (?flags:exp) set flags for exp (non-capturing)</span>
<span class="doccomment">//! </pre></span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Flags are each a single character. For example, `(?x)` sets the flag `x`</span>
<span class="doccomment">//! and `(?-x)` clears the flag `x`. Multiple flags can be set or cleared at</span>
<span class="doccomment">//! the same time: `(?xy)` sets both the `x` and `y` flags and `(?x-y)` sets</span>
<span class="doccomment">//! the `x` flag and clears the `y` flag.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! All flags are by default disabled unless stated otherwise. They are:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! <pre class="rust"></span>
<span class="doccomment">//! i case-insensitive</span>
<span class="doccomment">//! m multi-line mode: ^ and $ match begin/end of line</span>
<span class="doccomment">//! s allow . to match \n</span>
<span class="doccomment">//! U swap the meaning of x* and x*?</span>
<span class="doccomment">//! u Unicode support (enabled by default)</span>
<span class="doccomment">//! x ignore whitespace and allow line comments (starting with `#`)</span>
<span class="doccomment">//! </pre></span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Here's an example that matches case-insensitively for only part of the</span>
<span class="doccomment">//! expression:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! # extern crate regex; use regex::Regex;</span>
<span class="doccomment">//! # fn main() {</span>
<span class="doccomment">//! let re = Regex::new(r"(?i)a+(?-i)b+").unwrap();</span>
<span class="doccomment">//! let cap = re.captures("AaAaAbbBBBb").unwrap();</span>
<span class="doccomment">//! assert_eq!(cap.at(0), Some("AaAaAbb"));</span>
<span class="doccomment">//! # }</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Notice that the `a+` matches either `a` or `A`, but the `b+` only matches</span>
<span class="doccomment">//! `b`.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Here is an example that uses an ASCII word boundary instead of a Unicode</span>
<span class="doccomment">//! word boundary:</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ```rust</span>
<span class="doccomment">//! # extern crate regex; use regex::Regex;</span>
<span class="doccomment">//! # fn main() {</span>
<span class="doccomment">//! let re = Regex::new(r"(?-u:\b).+(?-u:\b)").unwrap();</span>
<span class="doccomment">//! let cap = re.captures("$$abc$$").unwrap();</span>
<span class="doccomment">//! assert_eq!(cap.at(0), Some("abc"));</span>
<span class="doccomment">//! # }</span>
<span class="doccomment">//! ```</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ## Escape sequences</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! <pre class="rust"></span>
<span class="doccomment">//! \* literal *, works for any punctuation character: \.+*?()|[]{}^$</span>
<span class="doccomment">//! \a bell (\x07)</span>
<span class="doccomment">//! \f form feed (\x0C)</span>
<span class="doccomment">//! \t horizontal tab</span>
<span class="doccomment">//! \n new line</span>
<span class="doccomment">//! \r carriage return</span>
<span class="doccomment">//! \v vertical tab (\x0B)</span>
<span class="doccomment">//! \123 octal character code (up to three digits)</span>
<span class="doccomment">//! \x7F hex character code (exactly two digits)</span>
<span class="doccomment">//! \x{10FFFF} any hex character code corresponding to a Unicode code point</span>
<span class="doccomment">//! </pre></span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ## Perl character classes (Unicode friendly)</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! These classes are based on the definitions provided in</span>
<span class="doccomment">//! [UTS#18](http://www.unicode.org/reports/tr18/#Compatibility_Properties):</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! <pre class="rust"></span>
<span class="doccomment">//! \d digit (\p{Nd})</span>
<span class="doccomment">//! \D not digit</span>
<span class="doccomment">//! \s whitespace (\p{White_Space})</span>
<span class="doccomment">//! \S not whitespace</span>
<span class="doccomment">//! \w word character (\p{Alphabetic} + \p{M} + \d + \p{Pc} + \p{Join_Control})</span>
<span class="doccomment">//! \W not word character</span>
<span class="doccomment">//! </pre></span>
<span class="doccomment">//!</span>
<span class="doccomment">//! ## ASCII character classes</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! <pre class="rust"></span>
<span class="doccomment">//! [:alnum:] alphanumeric ([0-9A-Za-z])</span>
<span class="doccomment">//! [:alpha:] alphabetic ([A-Za-z])</span>
<span class="doccomment">//! [:ascii:] ASCII ([\x00-\x7F])</span>
<span class="doccomment">//! [:blank:] blank ([\t ])</span>
<span class="doccomment">//! [:cntrl:] control ([\x00-\x1F\x7F])</span>
<span class="doccomment">//! [:digit:] digits ([0-9])</span>
<span class="doccomment">//! [:graph:] graphical ([!-~])</span>
<span class="doccomment">//! [:lower:] lower case ([a-z])</span>
<span class="doccomment">//! [:print:] printable ([ -~])</span>
<span class="doccomment">//! [:punct:] punctuation ([!-/:-@[-`{-~])</span>
<span class="doccomment">//! [:space:] whitespace ([\t\n\v\f\r ])</span>
<span class="doccomment">//! [:upper:] upper case ([A-Z])</span>
<span class="doccomment">//! [:word:] word characters ([0-9A-Za-z_])</span>
<span class="doccomment">//! [:xdigit:] hex digit ([0-9A-Fa-f])</span>
<span class="doccomment">//! </pre></span>
<span class="doccomment">//!</span>
<span class="doccomment">//! # Untrusted input</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! This crate can handle both untrusted regular expressions and untrusted</span>
<span class="doccomment">//! search text.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Untrusted regular expressions are handled by capping the size of a compiled</span>
<span class="doccomment">//! regular expression. (See `Regex::with_size_limit`.) Without this, it would</span>
<span class="doccomment">//! be trivial for an attacker to exhaust your system's memory with expressions</span>
<span class="doccomment">//! like `a{100}{100}{100}`.</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! Untrusted search text is allowed because the matching engine(s) in this</span>
<span class="doccomment">//! crate have time complexity `O(mn)` (with `m ~ regex` and `n ~ search</span>
<span class="doccomment">//! text`), which means there's no way to cause exponential blow-up like with</span>
<span class="doccomment">//! some other regular expression engines. (We pay for this by disallowing</span>
<span class="doccomment">//! features like arbitrary look-ahead and backreferences.)</span>
<span class="doccomment">//!</span>
<span class="doccomment">//! When a DFA is used, pathological cases with exponential state blow up are</span>
<span class="doccomment">//! avoided by constructing the DFA lazily or in an "online" manner. Therefore,</span>
<span class="doccomment">//! at most one new state can be created for each byte of input. This satisfies</span>
<span class="doccomment">//! our time complexity guarantees, but can lead to unbounded memory growth</span>
<span class="doccomment">//! proportional to the size of the input. As a stopgap, the DFA is only</span>
<span class="doccomment">//! allowed to store a fixed number of states. (When the limit is reached, its</span>
<span class="doccomment">//! states are wiped and continues on, possibly duplicating previous work. If</span>
<span class="doccomment">//! the limit is reached too frequently, it gives up and hands control off to</span>
<span class="doccomment">//! another matching engine with fixed memory requirements.)</span>
<span class="attribute">#<span class="op">!</span>[<span class="ident">deny</span>(<span class="ident">missing_docs</span>)]</span>
<span class="attribute">#<span class="op">!</span>[<span class="ident">cfg_attr</span>(<span class="ident">test</span>, <span class="ident">deny</span>(<span class="ident">warnings</span>))]</span>
<span class="attribute">#<span class="op">!</span>[<span class="ident">cfg_attr</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"pattern"</span>, <span class="ident">feature</span>(<span class="ident">pattern</span>))]</span>
<span class="attribute">#<span class="op">!</span>[<span class="ident">cfg_attr</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"simd-accel"</span>, <span class="ident">feature</span>(<span class="ident">cfg_target_feature</span>))]</span>
<span class="attribute">#<span class="op">!</span>[<span class="ident">doc</span>(<span class="ident">html_logo_url</span> <span class="op">=</span> <span class="string">"https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png"</span>,
<span class="ident">html_favicon_url</span> <span class="op">=</span> <span class="string">"https://www.rust-lang.org/favicon.ico"</span>,
<span class="ident">html_root_url</span> <span class="op">=</span> <span class="string">"https://doc.rust-lang.org/regex/"</span>)]</span>
<span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">aho_corasick</span>;
<span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">memchr</span>;
<span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">thread_local</span>;
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">test</span>)]</span> <span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">quickcheck</span>;
<span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">regex_syntax</span> <span class="kw">as</span> <span class="ident">syntax</span>;
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"simd-accel"</span>)]</span> <span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">simd</span>;
<span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">utf8_ranges</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">error</span>::<span class="ident">Error</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">re_builder</span>::<span class="ident">unicode</span>::<span class="kw-2">*</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">re_set</span>::<span class="ident">unicode</span>::<span class="kw-2">*</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">re_unicode</span>::{
<span class="ident">Regex</span>, <span class="ident">Captures</span>, <span class="ident">SubCaptures</span>, <span class="ident">SubCapturesPos</span>, <span class="ident">SubCapturesNamed</span>,
<span class="ident">CaptureNames</span>, <span class="ident">FindCaptures</span>, <span class="ident">FindMatches</span>,
<span class="ident">Replacer</span>, <span class="ident">NoExpand</span>, <span class="ident">RegexSplits</span>, <span class="ident">RegexSplitsN</span>,
<span class="ident">quote</span>, <span class="ident">is_match</span>,
};
<span class="doccomment">/**
Match regular expressions on arbitrary bytes.
This module provides a nearly identical API to the one found in the
top-level of this crate. There are two important differences:
1. Matching is done on `&[u8]` instead of `&str`. Additionally, `Vec<u8>`
is used where `String` would have been used.
2. Regular expressions are compiled with Unicode support *disabled* by
default. This means that while Unicode regular expressions can only match valid
UTF-8, regular expressions in this module can match arbitrary bytes. Unicode
support can be selectively enabled via the `u` flag in regular expressions
provided by this sub-module.
# Example: match null terminated string
This shows how to find all null-terminated strings in a slice of bytes:
```rust
# use regex::bytes::Regex;
let re = Regex::new(r"(?P<cstr>[^\x00]+)\x00").unwrap();
let text = b"foo\x00bar\x00baz\x00";
// Extract all of the strings without the null terminator from each match.
// The unwrap is OK here since a match requires the `cstr` capture to match.
let cstrs: Vec<&[u8]> =
re.captures_iter(text)
.map(|c| c.name("cstr").unwrap())
.collect();
assert_eq!(vec![&b"foo"[..], &b"bar"[..], &b"baz"[..]], cstrs);
```
# Example: selectively enable Unicode support
This shows how to match an arbitrary byte pattern followed by a UTF-8 encoded
string (e.g., to extract a title from a Matroska file):
```rust
# use std::str;
# use regex::bytes::Regex;
let re = Regex::new(r"\x7b\xa9(?:[\x80-\xfe]|[\x40-\xff].)(?u:(.*))").unwrap();
let text = b"\x12\xd0\x3b\x5f\x7b\xa9\x85\xe2\x98\x83\x80\x98\x54\x76\x68\x65";
let caps = re.captures(text).unwrap();
// Notice that despite the `.*` at the end, it will only match valid UTF-8
// because Unicode mode was enabled with the `u` flag. Without the `u` flag,
// the `.*` would match the rest of the bytes.
assert_eq!((7, 10), caps.pos(1).unwrap());
// If there was a match, Unicode mode guarantees that `title` is valid UTF-8.
let title = str::from_utf8(caps.at(1).unwrap()).unwrap();
assert_eq!("☃", title);
```
In general, if the Unicode flag is enabled in a capture group and that capture
is part of the overall match, then the capture is *guaranteed* to be valid
UTF-8.
# Syntax
The supported syntax is pretty much the same as the syntax for Unicode
regular expressions with a few changes that make sense for matching arbitrary
bytes:
1. The `u` flag is *disabled* by default, but can be selectively enabled. (The
opposite is true for the main `Regex` type.) Disabling the `u` flag is said to
invoke "ASCII compatible" mode.
2. In ASCII compatible mode, neither Unicode codepoints nor Unicode character
classes are allowed.
3. In ASCII compatible mode, Perl character classes (`\w`, `\d` and `\s`)
revert to their typical ASCII definition. `\w` maps to `[[:word:]]`, `\d` maps
to `[[:digit:]]` and `\s` maps to `[[:space:]]`.
4. In ASCII compatible mode, word boundaries use the ASCII compatible `\w` to
determine whether a byte is a word byte or not.
5. Hexadecimal notation can be used to specify arbitrary bytes instead of
Unicode codepoints. For example, in ASCII compatible mode, `\xFF` matches the
literal byte `\xFF`, while in Unicode mode, `\xFF` is a Unicode codepoint that
matches its UTF-8 encoding of `\xC3\xBF`. Similarly for octal notation.
6. `.` matches any *byte* except for `\n` instead of any codepoint. When the
`s` flag is enabled, `.` matches any byte.
# Performance
In general, one should expect performance on `&[u8]` to be roughly similar to
performance on `&str`.
*/</span>
<span class="kw">pub</span> <span class="kw">mod</span> <span class="ident">bytes</span> {
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">re_builder</span>::<span class="ident">bytes</span>::<span class="kw-2">*</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">re_set</span>::<span class="ident">bytes</span>::<span class="kw-2">*</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">re_bytes</span>::<span class="kw-2">*</span>;
}
<span class="kw">mod</span> <span class="ident">backtrack</span>;
<span class="kw">mod</span> <span class="ident">utf8</span>;
<span class="kw">mod</span> <span class="ident">compile</span>;
<span class="kw">mod</span> <span class="ident">dfa</span>;
<span class="kw">mod</span> <span class="ident">error</span>;
<span class="kw">mod</span> <span class="ident">exec</span>;
<span class="kw">mod</span> <span class="ident">expand</span>;
<span class="kw">mod</span> <span class="ident">freqs</span>;
<span class="kw">mod</span> <span class="ident">input</span>;
<span class="kw">mod</span> <span class="ident">literals</span>;
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"pattern"</span>)]</span>
<span class="kw">mod</span> <span class="ident">pattern</span>;
<span class="kw">mod</span> <span class="ident">pikevm</span>;
<span class="kw">mod</span> <span class="ident">prog</span>;
<span class="kw">mod</span> <span class="ident">re_builder</span>;
<span class="kw">mod</span> <span class="ident">re_bytes</span>;
<span class="kw">mod</span> <span class="ident">re_plugin</span>;
<span class="kw">mod</span> <span class="ident">re_set</span>;
<span class="kw">mod</span> <span class="ident">re_trait</span>;
<span class="kw">mod</span> <span class="ident">re_unicode</span>;
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"simd-accel"</span>)]</span>
<span class="kw">mod</span> <span class="ident">simd_accel</span>;
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">not</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"simd-accel"</span>))]</span>
<span class="attribute">#[<span class="ident">path</span> <span class="op">=</span> <span class="string">"simd_fallback/mod.rs"</span>]</span>
<span class="kw">mod</span> <span class="ident">simd_accel</span>;
<span class="kw">mod</span> <span class="ident">sparse</span>;
<span class="doccomment">/// The `internal` module exists to support the `regex!` macro and other</span>
<span class="doccomment">/// suspicious activity, such as testing different matching engines and</span>
<span class="doccomment">/// supporting the `regex-debug` CLI utility.</span>
<span class="attribute">#[<span class="ident">doc</span>(<span class="ident">hidden</span>)]</span>
<span class="kw">pub</span> <span class="kw">mod</span> <span class="ident">internal</span> {
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">compile</span>::<span class="ident">Compiler</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">exec</span>::{<span class="ident">Exec</span>, <span class="ident">ExecBuilder</span>};
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">input</span>::{<span class="ident">Char</span>, <span class="ident">Input</span>, <span class="ident">CharInput</span>, <span class="ident">InputAt</span>};
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">literals</span>::<span class="ident">LiteralSearcher</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">prog</span>::{<span class="ident">Program</span>, <span class="ident">Inst</span>, <span class="ident">EmptyLook</span>, <span class="ident">InstRanges</span>};
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">re_plugin</span>::<span class="ident">Plugin</span>;
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">re_unicode</span>::<span class="ident">_Regex</span>;
}
</pre>
</section>
<section id='search' class="content hidden"></section>
<section class="footer"></section>
<aside id="help" class="hidden">
<div>
<h1 class="hidden">Help</h1>
<div class="shortcuts">
<h2>Keyboard Shortcuts</h2>
<dl>
<dt>?</dt>
<dd>Show this help dialog</dd>
<dt>S</dt>
<dd>Focus the search field</dd>
<dt>⇤</dt>
<dd>Move up in search results</dd>
<dt>⇥</dt>
<dd>Move down in search results</dd>
<dt>⏎</dt>
<dd>Go to active search result</dd>
<dt>+</dt>
<dd>Collapse/expand all sections</dd>
</dl>
</div>
<div class="infos">
<h2>Search Tricks</h2>
<p>
Prefix searches with a type followed by a colon (e.g.
<code>fn:</code>) to restrict the search to a given type.
</p>
<p>
Accepted types are: <code>fn</code>, <code>mod</code>,
<code>struct</code>, <code>enum</code>,
<code>trait</code>, <code>type</code>, <code>macro</code>,
and <code>const</code>.
</p>
<p>
Search functions by type signature (e.g.
<code>vec -> usize</code> or <code>* -> vec</code>)
</p>
</div>
</div>
</aside>
<script>
window.rootPath = "../../";
window.currentCrate = "regex";
</script>
<script src="../../main.js"></script>
<script defer src="../../search-index.js"></script>
</body>
</html>