src/rustyline/completion.rs.html - third_party/rust-mirrors/rustyline - Git at Google

 <!DOCTYPE html>
 <html lang="en">
 <head>
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <meta name="generator" content="rustdoc">
     <meta name="description" content="Source to the Rust file `src/completion.rs`.">
     <meta name="keywords" content="rust, rustlang, rust-lang">

     <title>completion.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">


 </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">


     </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>
 </pre><pre class="rust ">
 <span class="doccomment">//! Completion API</span>
 <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">borrow</span>::<span class="ident">Cow</span>::{<span class="self">self</span>, <span class="ident">Borrowed</span>, <span class="ident">Owned</span>};
 <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">BTreeSet</span>;
 <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">fs</span>;
 <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">path</span>::{<span class="self">self</span>, <span class="ident">Path</span>};

 <span class="kw">use</span> <span class="kw">super</span>::<span class="prelude-ty">Result</span>;
 <span class="kw">use</span> <span class="ident">line_buffer</span>::<span class="ident">LineBuffer</span>;

 <span class="comment">// TODO: let the implementers choose/find word boudaries ???</span>
 <span class="comment">// (line, pos) is like (rl_line_buffer, rl_point) to make contextual completion (&quot;select t.na| from tbl as t&quot;)</span>
 <span class="comment">// TOOD: make &amp;self &amp;mut self ???</span>

 <span class="doccomment">/// To be called for tab-completion.</span>
 <span class="kw">pub</span> <span class="kw">trait</span> <span class="ident">Completer</span> {
     <span class="doccomment">/// Takes the currently edited `line` with the cursor `pos`ition and</span>
     <span class="doccomment">/// returns the start position and the completion candidates for the partial word to be completed.</span>
     <span class="doccomment">/// &quot;ls /usr/loc&quot; =&gt; Ok((3, vec![&quot;/usr/local/&quot;]))</span>
     <span class="kw">fn</span> <span class="ident">complete</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">line</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>, <span class="ident">pos</span>: <span class="ident">usize</span>) <span class="op">-&gt;</span> <span class="prelude-ty">Result</span><span class="op">&lt;</span>(<span class="ident">usize</span>, <span class="ident">Vec</span><span class="op">&lt;</span><span class="ident">String</span><span class="op">&gt;</span>)<span class="op">&gt;</span>;
     <span class="doccomment">/// Updates the edited `line` with the `elected` candidate.</span>
     <span class="kw">fn</span> <span class="ident">update</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">line</span>: <span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="ident">LineBuffer</span>, <span class="ident">start</span>: <span class="ident">usize</span>, <span class="ident">elected</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>) {
         <span class="kw">let</span> <span class="ident">end</span> <span class="op">=</span> <span class="ident">line</span>.<span class="ident">pos</span>();
         <span class="ident">line</span>.<span class="ident">replace</span>(<span class="ident">start</span>..<span class="ident">end</span>, <span class="ident">elected</span>)
     }
 }

 <span class="kw">impl</span> <span class="ident">Completer</span> <span class="kw">for</span> () {
     <span class="kw">fn</span> <span class="ident">complete</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">_line</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>, <span class="ident">_pos</span>: <span class="ident">usize</span>) <span class="op">-&gt;</span> <span class="prelude-ty">Result</span><span class="op">&lt;</span>(<span class="ident">usize</span>, <span class="ident">Vec</span><span class="op">&lt;</span><span class="ident">String</span><span class="op">&gt;</span>)<span class="op">&gt;</span> {
         <span class="prelude-val">Ok</span>((<span class="number">0</span>, <span class="ident">Vec</span>::<span class="ident">new</span>()))
     }
     <span class="kw">fn</span> <span class="ident">update</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">_line</span>: <span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="ident">LineBuffer</span>, <span class="ident">_start</span>: <span class="ident">usize</span>, <span class="ident">_elected</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>) {
         <span class="macro">unreachable</span><span class="macro">!</span>()
     }
 }

 <span class="kw">impl</span><span class="op">&lt;</span><span class="lifetime">&#39;c</span>, <span class="ident">C</span>: <span class="question-mark">?</span><span class="ident">Sized</span> <span class="op">+</span> <span class="ident">Completer</span><span class="op">&gt;</span> <span class="ident">Completer</span> <span class="kw">for</span> <span class="kw-2">&amp;</span><span class="lifetime">&#39;c</span> <span class="ident">C</span> {
     <span class="kw">fn</span> <span class="ident">complete</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">line</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>, <span class="ident">pos</span>: <span class="ident">usize</span>) <span class="op">-&gt;</span> <span class="prelude-ty">Result</span><span class="op">&lt;</span>(<span class="ident">usize</span>, <span class="ident">Vec</span><span class="op">&lt;</span><span class="ident">String</span><span class="op">&gt;</span>)<span class="op">&gt;</span> {
         (<span class="kw-2">*</span><span class="kw-2">*</span><span class="self">self</span>).<span class="ident">complete</span>(<span class="ident">line</span>, <span class="ident">pos</span>)
     }
     <span class="kw">fn</span> <span class="ident">update</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">line</span>: <span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="ident">LineBuffer</span>, <span class="ident">start</span>: <span class="ident">usize</span>, <span class="ident">elected</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>) {
         (<span class="kw-2">*</span><span class="kw-2">*</span><span class="self">self</span>).<span class="ident">update</span>(<span class="ident">line</span>, <span class="ident">start</span>, <span class="ident">elected</span>)
     }
 }
 <span class="macro">macro_rules</span><span class="macro">!</span> <span class="ident">box_completer</span> {
     ($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">id</span>: <span class="ident">ident</span>)<span class="kw-2">*</span>) <span class="op">=&gt;</span> {
         $(
             <span class="kw">impl</span><span class="op">&lt;</span><span class="ident">C</span>: <span class="question-mark">?</span><span class="ident">Sized</span> <span class="op">+</span> <span class="ident">Completer</span><span class="op">&gt;</span> <span class="ident">Completer</span> <span class="kw">for</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">id</span><span class="op">&lt;</span><span class="ident">C</span><span class="op">&gt;</span> {
                 <span class="kw">fn</span> <span class="ident">complete</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">line</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>, <span class="ident">pos</span>: <span class="ident">usize</span>) <span class="op">-&gt;</span> <span class="prelude-ty">Result</span><span class="op">&lt;</span>(<span class="ident">usize</span>, <span class="ident">Vec</span><span class="op">&lt;</span><span class="ident">String</span><span class="op">&gt;</span>)<span class="op">&gt;</span> {
                     (<span class="kw-2">*</span><span class="kw-2">*</span><span class="self">self</span>).<span class="ident">complete</span>(<span class="ident">line</span>, <span class="ident">pos</span>)
                 }
                 <span class="kw">fn</span> <span class="ident">update</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">line</span>: <span class="kw-2">&amp;</span><span class="kw-2">mut</span> <span class="ident">LineBuffer</span>, <span class="ident">start</span>: <span class="ident">usize</span>, <span class="ident">elected</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>) {
                     (<span class="kw-2">*</span><span class="kw-2">*</span><span class="self">self</span>).<span class="ident">update</span>(<span class="ident">line</span>, <span class="ident">start</span>, <span class="ident">elected</span>)
                 }
             }
         )<span class="op">*</span>
     }
 }

 <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">rc</span>::<span class="ident">Rc</span>;
 <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">sync</span>::<span class="ident">Arc</span>;
 <span class="macro">box_completer</span><span class="macro">!</span> { <span class="ident">Box</span> <span class="ident">Rc</span> <span class="ident">Arc</span> }

 <span class="doccomment">/// A `Completer` for file and folder names.</span>
 <span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">FilenameCompleter</span> {
     <span class="ident">break_chars</span>: <span class="ident">BTreeSet</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span>,
 }

 <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">unix</span>)]</span>
 <span class="kw">static</span> <span class="ident">DEFAULT_BREAK_CHARS</span>: [<span class="ident">char</span>; <span class="number">18</span>] <span class="op">=</span> [<span class="string">&#39; &#39;</span>, <span class="string">&#39;\t&#39;</span>, <span class="string">&#39;\n&#39;</span>, <span class="string">&#39;&quot;&#39;</span>, <span class="string">&#39;\\&#39;</span>, <span class="string">&#39;\&#39;&#39;</span>, <span class="string">&#39;`&#39;</span>, <span class="string">&#39;@&#39;</span>, <span class="string">&#39;$&#39;</span>, <span class="string">&#39;&gt;&#39;</span>,
                                           <span class="string">&#39;&lt;&#39;</span>, <span class="string">&#39;=&#39;</span>, <span class="string">&#39;;&#39;</span>, <span class="string">&#39;|&#39;</span>, <span class="string">&#39;&amp;&#39;</span>, <span class="string">&#39;{&#39;</span>, <span class="string">&#39;(&#39;</span>, <span class="string">&#39;\0&#39;</span>];
 <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">unix</span>)]</span>
 <span class="kw">static</span> <span class="ident">ESCAPE_CHAR</span>: <span class="prelude-ty">Option</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span> <span class="op">=</span> <span class="prelude-val">Some</span>(<span class="string">&#39;\\&#39;</span>);
 <span class="comment">// Remove \ to make file completion works on windows</span>
 <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">windows</span>)]</span>
 <span class="kw">static</span> <span class="ident">DEFAULT_BREAK_CHARS</span>: [<span class="ident">char</span>; <span class="number">17</span>] <span class="op">=</span> [<span class="string">&#39; &#39;</span>, <span class="string">&#39;\t&#39;</span>, <span class="string">&#39;\n&#39;</span>, <span class="string">&#39;&quot;&#39;</span>, <span class="string">&#39;\&#39;&#39;</span>, <span class="string">&#39;`&#39;</span>, <span class="string">&#39;@&#39;</span>, <span class="string">&#39;$&#39;</span>, <span class="string">&#39;&gt;&#39;</span>, <span class="string">&#39;&lt;&#39;</span>,
                                           <span class="string">&#39;=&#39;</span>, <span class="string">&#39;;&#39;</span>, <span class="string">&#39;|&#39;</span>, <span class="string">&#39;&amp;&#39;</span>, <span class="string">&#39;{&#39;</span>, <span class="string">&#39;(&#39;</span>, <span class="string">&#39;\0&#39;</span>];
 <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">windows</span>)]</span>
 <span class="kw">static</span> <span class="ident">ESCAPE_CHAR</span>: <span class="prelude-ty">Option</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span> <span class="op">=</span> <span class="prelude-val">None</span>;

 <span class="kw">impl</span> <span class="ident">FilenameCompleter</span> {
     <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">new</span>() <span class="op">-&gt;</span> <span class="ident">FilenameCompleter</span> {
         <span class="ident">FilenameCompleter</span> { <span class="ident">break_chars</span>: <span class="ident">DEFAULT_BREAK_CHARS</span>.<span class="ident">iter</span>().<span class="ident">cloned</span>().<span class="ident">collect</span>() }
     }
 }

 <span class="kw">impl</span> <span class="ident">Default</span> <span class="kw">for</span> <span class="ident">FilenameCompleter</span> {
     <span class="kw">fn</span> <span class="ident">default</span>() <span class="op">-&gt;</span> <span class="ident">FilenameCompleter</span> {
         <span class="ident">FilenameCompleter</span>::<span class="ident">new</span>()
     }
 }

 <span class="kw">impl</span> <span class="ident">Completer</span> <span class="kw">for</span> <span class="ident">FilenameCompleter</span> {
     <span class="kw">fn</span> <span class="ident">complete</span>(<span class="kw-2">&amp;</span><span class="self">self</span>, <span class="ident">line</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>, <span class="ident">pos</span>: <span class="ident">usize</span>) <span class="op">-&gt;</span> <span class="prelude-ty">Result</span><span class="op">&lt;</span>(<span class="ident">usize</span>, <span class="ident">Vec</span><span class="op">&lt;</span><span class="ident">String</span><span class="op">&gt;</span>)<span class="op">&gt;</span> {
         <span class="kw">let</span> (<span class="ident">start</span>, <span class="ident">path</span>) <span class="op">=</span> <span class="ident">extract_word</span>(<span class="ident">line</span>, <span class="ident">pos</span>, <span class="ident">ESCAPE_CHAR</span>, <span class="kw-2">&amp;</span><span class="self">self</span>.<span class="ident">break_chars</span>);
         <span class="kw">let</span> <span class="ident">path</span> <span class="op">=</span> <span class="ident">unescape</span>(<span class="ident">path</span>, <span class="ident">ESCAPE_CHAR</span>);
         <span class="kw">let</span> <span class="ident">matches</span> <span class="op">=</span> <span class="macro">try</span><span class="macro">!</span>(<span class="ident">filename_complete</span>(<span class="kw-2">&amp;</span><span class="ident">path</span>, <span class="ident">ESCAPE_CHAR</span>, <span class="kw-2">&amp;</span><span class="self">self</span>.<span class="ident">break_chars</span>));
         <span class="prelude-val">Ok</span>((<span class="ident">start</span>, <span class="ident">matches</span>))
     }
 }

 <span class="doccomment">/// Remove escape char</span>
 <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">unescape</span>(<span class="ident">input</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>, <span class="ident">esc_char</span>: <span class="prelude-ty">Option</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span>) <span class="op">-&gt;</span> <span class="ident">Cow</span><span class="op">&lt;</span><span class="ident">str</span><span class="op">&gt;</span> {
     <span class="kw">if</span> <span class="ident">esc_char</span>.<span class="ident">is_none</span>() {
         <span class="kw">return</span> <span class="ident">Borrowed</span>(<span class="ident">input</span>);
     }
     <span class="kw">let</span> <span class="ident">esc_char</span> <span class="op">=</span> <span class="ident">esc_char</span>.<span class="ident">unwrap</span>();
     <span class="kw">let</span> <span class="ident">n</span> <span class="op">=</span> <span class="ident">input</span>.<span class="ident">chars</span>().<span class="ident">filter</span>(<span class="op">|</span><span class="kw-2">&amp;</span><span class="ident">c</span><span class="op">|</span> <span class="ident">c</span> <span class="op">==</span> <span class="ident">esc_char</span>).<span class="ident">count</span>();
     <span class="kw">if</span> <span class="ident">n</span> <span class="op">==</span> <span class="number">0</span> {
         <span class="kw">return</span> <span class="ident">Borrowed</span>(<span class="ident">input</span>);
     }
     <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">result</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">with_capacity</span>(<span class="ident">input</span>.<span class="ident">len</span>() <span class="op">-</span> <span class="ident">n</span>);
     <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">chars</span> <span class="op">=</span> <span class="ident">input</span>.<span class="ident">chars</span>();
     <span class="kw">while</span> <span class="kw">let</span> <span class="prelude-val">Some</span>(<span class="ident">ch</span>) <span class="op">=</span> <span class="ident">chars</span>.<span class="ident">next</span>() {
         <span class="kw">if</span> <span class="ident">ch</span> <span class="op">==</span> <span class="ident">esc_char</span> {
             <span class="kw">if</span> <span class="kw">let</span> <span class="prelude-val">Some</span>(<span class="ident">ch</span>) <span class="op">=</span> <span class="ident">chars</span>.<span class="ident">next</span>() {
                 <span class="ident">result</span>.<span class="ident">push</span>(<span class="ident">ch</span>);
             }
         } <span class="kw">else</span> {
             <span class="ident">result</span>.<span class="ident">push</span>(<span class="ident">ch</span>);
         }
     }
     <span class="ident">Owned</span>(<span class="ident">result</span>)
 }

 <span class="doccomment">/// Escape any `break_chars` in `input` string with `esc_char`.</span>
 <span class="doccomment">/// For example, &#39;/User Information&#39; becomes &#39;/User\ Information&#39;</span>
 <span class="doccomment">/// when space is a breaking char and &#39;\&#39; the escape char.</span>
 <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">escape</span>(<span class="ident">input</span>: <span class="ident">String</span>, <span class="ident">esc_char</span>: <span class="prelude-ty">Option</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span>, <span class="ident">break_chars</span>: <span class="kw-2">&amp;</span><span class="ident">BTreeSet</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span>) <span class="op">-&gt;</span> <span class="ident">String</span> {
     <span class="kw">if</span> <span class="ident">esc_char</span>.<span class="ident">is_none</span>() {
         <span class="kw">return</span> <span class="ident">input</span>;
     }
     <span class="kw">let</span> <span class="ident">esc_char</span> <span class="op">=</span> <span class="ident">esc_char</span>.<span class="ident">unwrap</span>();
     <span class="kw">let</span> <span class="ident">n</span> <span class="op">=</span> <span class="ident">input</span>
         .<span class="ident">chars</span>()
         .<span class="ident">filter</span>(<span class="op">|</span><span class="ident">c</span><span class="op">|</span> <span class="ident">break_chars</span>.<span class="ident">contains</span>(<span class="ident">c</span>))
         .<span class="ident">count</span>();
     <span class="kw">if</span> <span class="ident">n</span> <span class="op">==</span> <span class="number">0</span> {
         <span class="kw">return</span> <span class="ident">input</span>;
     }
     <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">result</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">with_capacity</span>(<span class="ident">input</span>.<span class="ident">len</span>() <span class="op">+</span> <span class="ident">n</span>);

     <span class="kw">for</span> <span class="ident">c</span> <span class="kw">in</span> <span class="ident">input</span>.<span class="ident">chars</span>() {
         <span class="kw">if</span> <span class="ident">break_chars</span>.<span class="ident">contains</span>(<span class="kw-2">&amp;</span><span class="ident">c</span>) {
             <span class="ident">result</span>.<span class="ident">push</span>(<span class="ident">esc_char</span>);
         }
         <span class="ident">result</span>.<span class="ident">push</span>(<span class="ident">c</span>);
     }
     <span class="ident">result</span>
 }

 <span class="kw">fn</span> <span class="ident">filename_complete</span>(<span class="ident">path</span>: <span class="kw-2">&amp;</span><span class="ident">str</span>,
                      <span class="ident">esc_char</span>: <span class="prelude-ty">Option</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span>,
                      <span class="ident">break_chars</span>: <span class="kw-2">&amp;</span><span class="ident">BTreeSet</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span>)
                      <span class="op">-&gt;</span> <span class="prelude-ty">Result</span><span class="op">&lt;</span><span class="ident">Vec</span><span class="op">&lt;</span><span class="ident">String</span><span class="op">&gt;&gt;</span> {
     <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">env</span>::{<span class="ident">current_dir</span>, <span class="ident">home_dir</span>};

     <span class="kw">let</span> <span class="ident">sep</span> <span class="op">=</span> <span class="ident">path</span>::<span class="ident">MAIN_SEPARATOR</span>;
     <span class="kw">let</span> (<span class="ident">dir_name</span>, <span class="ident">file_name</span>) <span class="op">=</span> <span class="kw">match</span> <span class="ident">path</span>.<span class="ident">rfind</span>(<span class="ident">sep</span>) {
         <span class="prelude-val">Some</span>(<span class="ident">idx</span>) <span class="op">=&gt;</span> <span class="ident">path</span>.<span class="ident">split_at</span>(<span class="ident">idx</span> <span class="op">+</span> <span class="ident">sep</span>.<span class="ident">len_utf8</span>()),
         <span class="prelude-val">None</span> <span class="op">=&gt;</span> (<span class="string">&quot;&quot;</span>, <span class="ident">path</span>),
     };

     <span class="kw">let</span> <span class="ident">dir_path</span> <span class="op">=</span> <span class="ident">Path</span>::<span class="ident">new</span>(<span class="ident">dir_name</span>);
     <span class="kw">let</span> <span class="ident">dir</span> <span class="op">=</span> <span class="kw">if</span> <span class="ident">dir_path</span>.<span class="ident">starts_with</span>(<span class="string">&quot;~&quot;</span>) {
         <span class="comment">// ~[/...]</span>
         <span class="kw">if</span> <span class="kw">let</span> <span class="prelude-val">Some</span>(<span class="ident">home</span>) <span class="op">=</span> <span class="ident">home_dir</span>() {
             <span class="kw">match</span> <span class="ident">dir_path</span>.<span class="ident">strip_prefix</span>(<span class="string">&quot;~&quot;</span>) {
                 <span class="prelude-val">Ok</span>(<span class="ident">rel_path</span>) <span class="op">=&gt;</span> <span class="ident">home</span>.<span class="ident">join</span>(<span class="ident">rel_path</span>),
                 _ <span class="op">=&gt;</span> <span class="ident">home</span>,
             }
         } <span class="kw">else</span> {
             <span class="ident">dir_path</span>.<span class="ident">to_path_buf</span>()
         }
     } <span class="kw">else</span> <span class="kw">if</span> <span class="ident">dir_path</span>.<span class="ident">is_relative</span>() {
         <span class="comment">// TODO ~user[/...] (https://crates.io/crates/users)</span>
         <span class="kw">if</span> <span class="kw">let</span> <span class="prelude-val">Ok</span>(<span class="ident">cwd</span>) <span class="op">=</span> <span class="ident">current_dir</span>() {
             <span class="ident">cwd</span>.<span class="ident">join</span>(<span class="ident">dir_path</span>)
         } <span class="kw">else</span> {
             <span class="ident">dir_path</span>.<span class="ident">to_path_buf</span>()
         }
     } <span class="kw">else</span> {
         <span class="ident">dir_path</span>.<span class="ident">to_path_buf</span>()
     };

     <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">entries</span>: <span class="ident">Vec</span><span class="op">&lt;</span><span class="ident">String</span><span class="op">&gt;</span> <span class="op">=</span> <span class="ident">Vec</span>::<span class="ident">new</span>();
     <span class="kw">for</span> <span class="ident">entry</span> <span class="kw">in</span> <span class="macro">try</span><span class="macro">!</span>(<span class="ident">dir</span>.<span class="ident">read_dir</span>()) {
         <span class="kw">let</span> <span class="ident">entry</span> <span class="op">=</span> <span class="macro">try</span><span class="macro">!</span>(<span class="ident">entry</span>);
         <span class="kw">if</span> <span class="kw">let</span> <span class="prelude-val">Some</span>(<span class="ident">s</span>) <span class="op">=</span> <span class="ident">entry</span>.<span class="ident">file_name</span>().<span class="ident">to_str</span>() {
             <span class="kw">if</span> <span class="ident">s</span>.<span class="ident">starts_with</span>(<span class="ident">file_name</span>) {
                 <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">path</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from</span>(<span class="ident">dir_name</span>) <span class="op">+</span> <span class="ident">s</span>;
                 <span class="kw">if</span> <span class="macro">try</span><span class="macro">!</span>(<span class="ident">fs</span>::<span class="ident">metadata</span>(<span class="ident">entry</span>.<span class="ident">path</span>())).<span class="ident">is_dir</span>() {
                     <span class="ident">path</span>.<span class="ident">push</span>(<span class="ident">sep</span>);
                 }
                 <span class="ident">entries</span>.<span class="ident">push</span>(<span class="ident">escape</span>(<span class="ident">path</span>, <span class="ident">esc_char</span>, <span class="ident">break_chars</span>));
             }
         }
     }
     <span class="prelude-val">Ok</span>(<span class="ident">entries</span>)
 }

 <span class="doccomment">/// Given a `line` and a cursor `pos`ition,</span>
 <span class="doccomment">/// try to find backward the start of a word.</span>
 <span class="doccomment">/// Return (0, `line[..pos]`) if no break char has been found.</span>
 <span class="doccomment">/// Return the word and its start position (idx, `line[idx..pos]`) otherwise.</span>
 <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">extract_word</span><span class="op">&lt;</span><span class="lifetime">&#39;l</span><span class="op">&gt;</span>(<span class="ident">line</span>: <span class="kw-2">&amp;</span><span class="lifetime">&#39;l</span> <span class="ident">str</span>,
                         <span class="ident">pos</span>: <span class="ident">usize</span>,
                         <span class="ident">esc_char</span>: <span class="prelude-ty">Option</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span>,
                         <span class="ident">break_chars</span>: <span class="kw-2">&amp;</span><span class="ident">BTreeSet</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span>)
                         <span class="op">-&gt;</span> (<span class="ident">usize</span>, <span class="kw-2">&amp;</span><span class="lifetime">&#39;l</span> <span class="ident">str</span>) {
     <span class="kw">let</span> <span class="ident">line</span> <span class="op">=</span> <span class="kw-2">&amp;</span><span class="ident">line</span>[..<span class="ident">pos</span>];
     <span class="kw">if</span> <span class="ident">line</span>.<span class="ident">is_empty</span>() {
         <span class="kw">return</span> (<span class="number">0</span>, <span class="ident">line</span>);
     }
     <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">start</span> <span class="op">=</span> <span class="prelude-val">None</span>;
     <span class="kw">for</span> (<span class="ident">i</span>, <span class="ident">c</span>) <span class="kw">in</span> <span class="ident">line</span>.<span class="ident">char_indices</span>().<span class="ident">rev</span>() {
         <span class="kw">if</span> <span class="ident">esc_char</span>.<span class="ident">is_some</span>() <span class="op">&amp;&amp;</span> <span class="ident">start</span>.<span class="ident">is_some</span>() {
             <span class="kw">if</span> <span class="ident">esc_char</span>.<span class="ident">unwrap</span>() <span class="op">==</span> <span class="ident">c</span> {
                 <span class="comment">// escaped break char</span>
                 <span class="ident">start</span> <span class="op">=</span> <span class="prelude-val">None</span>;
                 <span class="kw">continue</span>;
             } <span class="kw">else</span> {
                 <span class="kw">break</span>;
             }
         }
         <span class="kw">if</span> <span class="ident">break_chars</span>.<span class="ident">contains</span>(<span class="kw-2">&amp;</span><span class="ident">c</span>) {
             <span class="ident">start</span> <span class="op">=</span> <span class="prelude-val">Some</span>(<span class="ident">i</span> <span class="op">+</span> <span class="ident">c</span>.<span class="ident">len_utf8</span>());
             <span class="kw">if</span> <span class="ident">esc_char</span>.<span class="ident">is_none</span>() {
                 <span class="kw">break</span>;
             } <span class="comment">// else maybe escaped...</span>
         }
     }

     <span class="kw">match</span> <span class="ident">start</span> {
         <span class="prelude-val">Some</span>(<span class="ident">start</span>) <span class="op">=&gt;</span> (<span class="ident">start</span>, <span class="kw-2">&amp;</span><span class="ident">line</span>[<span class="ident">start</span>..]),
         <span class="prelude-val">None</span> <span class="op">=&gt;</span> (<span class="number">0</span>, <span class="ident">line</span>),
     }
 }

 <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">longest_common_prefix</span>(<span class="ident">candidates</span>: <span class="kw-2">&amp;</span>[<span class="ident">String</span>]) <span class="op">-&gt;</span> <span class="prelude-ty">Option</span><span class="op">&lt;</span><span class="kw-2">&amp;</span><span class="ident">str</span><span class="op">&gt;</span> {
     <span class="kw">if</span> <span class="ident">candidates</span>.<span class="ident">is_empty</span>() {
         <span class="kw">return</span> <span class="prelude-val">None</span>;
     } <span class="kw">else</span> <span class="kw">if</span> <span class="ident">candidates</span>.<span class="ident">len</span>() <span class="op">==</span> <span class="number">1</span> {
         <span class="kw">return</span> <span class="prelude-val">Some</span>(<span class="kw-2">&amp;</span><span class="ident">candidates</span>[<span class="number">0</span>]);
     }
     <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">longest_common_prefix</span> <span class="op">=</span> <span class="number">0</span>;
     <span class="lifetime">&#39;o</span>: <span class="kw">loop</span> {
         <span class="kw">for</span> (<span class="ident">i</span>, <span class="ident">c1</span>) <span class="kw">in</span> <span class="ident">candidates</span>.<span class="ident">iter</span>().<span class="ident">enumerate</span>().<span class="ident">take</span>(<span class="ident">candidates</span>.<span class="ident">len</span>() <span class="op">-</span> <span class="number">1</span>) {
             <span class="kw">let</span> <span class="ident">b1</span> <span class="op">=</span> <span class="ident">c1</span>.<span class="ident">as_bytes</span>();
             <span class="kw">let</span> <span class="ident">b2</span> <span class="op">=</span> <span class="ident">candidates</span>[<span class="ident">i</span> <span class="op">+</span> <span class="number">1</span>].<span class="ident">as_bytes</span>();
             <span class="kw">if</span> <span class="ident">b1</span>.<span class="ident">len</span>() <span class="op">&lt;=</span> <span class="ident">longest_common_prefix</span> <span class="op">||</span> <span class="ident">b2</span>.<span class="ident">len</span>() <span class="op">&lt;=</span> <span class="ident">longest_common_prefix</span> <span class="op">||</span>
                <span class="ident">b1</span>[<span class="ident">longest_common_prefix</span>] <span class="op">!=</span> <span class="ident">b2</span>[<span class="ident">longest_common_prefix</span>] {
                 <span class="kw">break</span> <span class="lifetime">&#39;o</span>;
             }
         }
         <span class="ident">longest_common_prefix</span> <span class="op">+=</span> <span class="number">1</span>;
     }
     <span class="kw">while</span> <span class="op">!</span><span class="ident">candidates</span>[<span class="number">0</span>].<span class="ident">is_char_boundary</span>(<span class="ident">longest_common_prefix</span>) {
         <span class="ident">longest_common_prefix</span> <span class="op">-=</span> <span class="number">1</span>;
     }
     <span class="kw">if</span> <span class="ident">longest_common_prefix</span> <span class="op">==</span> <span class="number">0</span> {
         <span class="kw">return</span> <span class="prelude-val">None</span>;
     }
     <span class="prelude-val">Some</span>(<span class="kw-2">&amp;</span><span class="ident">candidates</span>[<span class="number">0</span>][<span class="number">0</span>..<span class="ident">longest_common_prefix</span>])
 }

 <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">test</span>)]</span>
 <span class="kw">mod</span> <span class="ident">tests</span> {
     <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">BTreeSet</span>;

     <span class="attribute">#[<span class="ident">test</span>]</span>
     <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">extract_word</span>() {
         <span class="kw">let</span> <span class="ident">break_chars</span>: <span class="ident">BTreeSet</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span> <span class="op">=</span> <span class="kw">super</span>::<span class="ident">DEFAULT_BREAK_CHARS</span>.<span class="ident">iter</span>().<span class="ident">cloned</span>().<span class="ident">collect</span>();
         <span class="kw">let</span> <span class="ident">line</span> <span class="op">=</span> <span class="string">&quot;ls &#39;/usr/local/b&quot;</span>;
         <span class="macro">assert_eq</span><span class="macro">!</span>((<span class="number">4</span>, <span class="string">&quot;/usr/local/b&quot;</span>),
                    <span class="kw">super</span>::<span class="ident">extract_word</span>(<span class="ident">line</span>, <span class="ident">line</span>.<span class="ident">len</span>(), <span class="prelude-val">Some</span>(<span class="string">&#39;\\&#39;</span>), <span class="kw-2">&amp;</span><span class="ident">break_chars</span>));
         <span class="kw">let</span> <span class="ident">line</span> <span class="op">=</span> <span class="string">&quot;ls /User\\ Information&quot;</span>;
         <span class="macro">assert_eq</span><span class="macro">!</span>((<span class="number">3</span>, <span class="string">&quot;/User\\ Information&quot;</span>),
                    <span class="kw">super</span>::<span class="ident">extract_word</span>(<span class="ident">line</span>, <span class="ident">line</span>.<span class="ident">len</span>(), <span class="prelude-val">Some</span>(<span class="string">&#39;\\&#39;</span>), <span class="kw-2">&amp;</span><span class="ident">break_chars</span>));
     }

     <span class="attribute">#[<span class="ident">test</span>]</span>
     <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">unescape</span>() {
         <span class="kw">use</span> <span class="ident">std</span>::<span class="ident">borrow</span>::<span class="ident">Cow</span>::{<span class="self">self</span>, <span class="ident">Borrowed</span>, <span class="ident">Owned</span>};
         <span class="kw">let</span> <span class="ident">input</span> <span class="op">=</span> <span class="string">&quot;/usr/local/b&quot;</span>;
         <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">Borrowed</span>(<span class="ident">input</span>), <span class="kw">super</span>::<span class="ident">unescape</span>(<span class="ident">input</span>, <span class="prelude-val">Some</span>(<span class="string">&#39;\\&#39;</span>)));
         <span class="kw">let</span> <span class="ident">input</span> <span class="op">=</span> <span class="string">&quot;/User\\ Information&quot;</span>;
         <span class="kw">let</span> <span class="ident">result</span>: <span class="ident">Cow</span><span class="op">&lt;</span><span class="ident">str</span><span class="op">&gt;</span> <span class="op">=</span> <span class="ident">Owned</span>(<span class="ident">String</span>::<span class="ident">from</span>(<span class="string">&quot;/User Information&quot;</span>));
         <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">result</span>, <span class="kw">super</span>::<span class="ident">unescape</span>(<span class="ident">input</span>, <span class="prelude-val">Some</span>(<span class="string">&#39;\\&#39;</span>)));
     }

     <span class="attribute">#[<span class="ident">test</span>]</span>
     <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">escape</span>() {
         <span class="kw">let</span> <span class="ident">break_chars</span>: <span class="ident">BTreeSet</span><span class="op">&lt;</span><span class="ident">char</span><span class="op">&gt;</span> <span class="op">=</span> <span class="kw">super</span>::<span class="ident">DEFAULT_BREAK_CHARS</span>.<span class="ident">iter</span>().<span class="ident">cloned</span>().<span class="ident">collect</span>();
         <span class="kw">let</span> <span class="ident">input</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from</span>(<span class="string">&quot;/usr/local/b&quot;</span>);
         <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">input</span>.<span class="ident">clone</span>(),
                    <span class="kw">super</span>::<span class="ident">escape</span>(<span class="ident">input</span>, <span class="prelude-val">Some</span>(<span class="string">&#39;\\&#39;</span>), <span class="kw-2">&amp;</span><span class="ident">break_chars</span>));
         <span class="kw">let</span> <span class="ident">input</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from</span>(<span class="string">&quot;/User Information&quot;</span>);
         <span class="kw">let</span> <span class="ident">result</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from</span>(<span class="string">&quot;/User\\ Information&quot;</span>);
         <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">result</span>, <span class="kw">super</span>::<span class="ident">escape</span>(<span class="ident">input</span>, <span class="prelude-val">Some</span>(<span class="string">&#39;\\&#39;</span>), <span class="kw-2">&amp;</span><span class="ident">break_chars</span>));
     }

     <span class="attribute">#[<span class="ident">test</span>]</span>
     <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">longest_common_prefix</span>() {
         <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">candidates</span> <span class="op">=</span> <span class="macro">vec</span><span class="macro">!</span>[];
         {
             <span class="kw">let</span> <span class="ident">lcp</span> <span class="op">=</span> <span class="kw">super</span>::<span class="ident">longest_common_prefix</span>(<span class="kw-2">&amp;</span><span class="ident">candidates</span>);
             <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">lcp</span>.<span class="ident">is_none</span>());
         }

         <span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="string">&quot;User&quot;</span>;
         <span class="kw">let</span> <span class="ident">c1</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from</span>(<span class="ident">s</span>);
         <span class="ident">candidates</span>.<span class="ident">push</span>(<span class="ident">c1</span>.<span class="ident">clone</span>());
         {
             <span class="kw">let</span> <span class="ident">lcp</span> <span class="op">=</span> <span class="kw">super</span>::<span class="ident">longest_common_prefix</span>(<span class="kw-2">&amp;</span><span class="ident">candidates</span>);
             <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="ident">s</span>), <span class="ident">lcp</span>);
         }

         <span class="kw">let</span> <span class="ident">c2</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from</span>(<span class="string">&quot;Users&quot;</span>);
         <span class="ident">candidates</span>.<span class="ident">push</span>(<span class="ident">c2</span>.<span class="ident">clone</span>());
         {
             <span class="kw">let</span> <span class="ident">lcp</span> <span class="op">=</span> <span class="kw">super</span>::<span class="ident">longest_common_prefix</span>(<span class="kw-2">&amp;</span><span class="ident">candidates</span>);
             <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="ident">s</span>), <span class="ident">lcp</span>);
         }

         <span class="kw">let</span> <span class="ident">c3</span> <span class="op">=</span> <span class="ident">String</span>::<span class="ident">from</span>(<span class="string">&quot;&quot;</span>);
         <span class="ident">candidates</span>.<span class="ident">push</span>(<span class="ident">c3</span>.<span class="ident">clone</span>());
         {
             <span class="kw">let</span> <span class="ident">lcp</span> <span class="op">=</span> <span class="kw">super</span>::<span class="ident">longest_common_prefix</span>(<span class="kw-2">&amp;</span><span class="ident">candidates</span>);
             <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">lcp</span>.<span class="ident">is_none</span>());
         }

         <span class="kw">let</span> <span class="ident">candidates</span> <span class="op">=</span> <span class="macro">vec</span><span class="macro">!</span>[<span class="ident">String</span>::<span class="ident">from</span>(<span class="string">&quot;fée&quot;</span>), <span class="ident">String</span>::<span class="ident">from</span>(<span class="string">&quot;fête&quot;</span>)];
         <span class="kw">let</span> <span class="ident">lcp</span> <span class="op">=</span> <span class="kw">super</span>::<span class="ident">longest_common_prefix</span>(<span class="kw-2">&amp;</span><span class="ident">candidates</span>);
         <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="prelude-val">Some</span>(<span class="string">&quot;f&quot;</span>), <span class="ident">lcp</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>&larrb;</dt>
                     <dd>Move up in search results</dd>
                     <dt>&rarrb;</dt>
                     <dd>Move down in search results</dd>
                     <dt>&#9166;</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 = "rustyline";
     </script>
     <script src="../../main.js"></script>
     <script defer src="../../search-index.js"></script>
 </body>
 </html>