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<div id="column1" data-id="punycode" class="interior"> 90 <header> 91 <div class="header-container"> 92 <h1>Node.js v14.21.2 documentation</h1> 93 <button class="theme-toggle-btn" id="theme-toggle-btn" title="Toggle dark mode/light mode" aria-label="Toggle dark mode/light mode" hidden> 94 <svg xmlns="http://www.w3.org/2000/svg" class="icon dark-icon" height="24" width="24"> 95 <path fill="none" d="M0 0h24v24H0z" /> 96 <path d="M11.1 12.08c-2.33-4.51-.5-8.48.53-10.07C6.27 2.2 1.98 6.59 1.98 12c0 .14.02.28.02.42.62-.27 1.29-.42 2-.42 1.66 0 3.18.83 4.1 2.15A4.01 4.01 0 0111 18c0 1.52-.87 2.83-2.12 3.51.98.32 2.03.5 3.11.5 3.5 0 6.58-1.8 8.37-4.52-2.36.23-6.98-.97-9.26-5.41z"/> 97 <path d="M7 16h-.18C6.4 14.84 5.3 14 4 14c-1.66 0-3 1.34-3 3s1.34 3 3 3h3c1.1 0 2-.9 2-2s-.9-2-2-2z"/> 98 </svg> 99 <svg xmlns="http://www.w3.org/2000/svg" class="icon light-icon" height="24" width="24"> 100 <path d="M0 0h24v24H0z" fill="none" /> 101 <path d="M6.76 4.84l-1.8-1.79-1.41 1.41 1.79 1.79 1.42-1.41zM4 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href="https://nodejs.org/docs/latest-v5.x/api/punycode.html">5.x</a></li> 134<li><a href="https://nodejs.org/docs/latest-v4.x/api/punycode.html">4.x</a></li> 135<li><a href="https://nodejs.org/docs/latest-v0.12.x/api/punycode.html">0.12.x</a></li> 136<li><a href="https://nodejs.org/docs/latest-v0.10.x/api/punycode.html">0.10.x</a></li></ol> 137 </li> 138 139 <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/master/doc/api/punycode.md">Edit on GitHub</a></li> 140 </ul> 141 </div> 142 <hr> 143 </header> 144 145 <details id="toc" open><summary>Table of contents</summary><ul> 146<li><span class="stability_0"><a href="#punycode_punycode">Punycode</a></span> 147<ul> 148<li><a href="#punycode_punycode_decode_string"><code>punycode.decode(string)</code></a></li> 149<li><a href="#punycode_punycode_encode_string"><code>punycode.encode(string)</code></a></li> 150<li><a href="#punycode_punycode_toascii_domain"><code>punycode.toASCII(domain)</code></a></li> 151<li><a href="#punycode_punycode_tounicode_domain"><code>punycode.toUnicode(domain)</code></a></li> 152<li><a href="#punycode_punycode_ucs2"><code>punycode.ucs2</code></a> 153<ul> 154<li><a href="#punycode_punycode_ucs2_decode_string"><code>punycode.ucs2.decode(string)</code></a></li> 155<li><a href="#punycode_punycode_ucs2_encode_codepoints"><code>punycode.ucs2.encode(codePoints)</code></a></li> 156</ul> 157</li> 158<li><a href="#punycode_punycode_version"><code>punycode.version</code></a></li> 159</ul> 160</li> 161</ul></details> 162 163 <div id="apicontent"> 164 <h2>Punycode<span><a class="mark" href="#punycode_punycode" id="punycode_punycode">#</a></span></h2> 165<div class="api_metadata"> 166<span>Deprecated since: v7.0.0</span> 167</div> 168 169<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated</div><p></p> 170<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v14.21.2/lib/punycode.js">lib/punycode.js</a></p> 171<p><strong>The version of the punycode module bundled in Node.js is being deprecated</strong>. 172In a future major version of Node.js this module will be removed. Users 173currently depending on the <code>punycode</code> module should switch to using the 174userland-provided <a href="https://github.com/bestiejs/punycode.js">Punycode.js</a> module instead. For punycode-based URL 175encoding, see <a href="url.html#url_url_domaintoascii_domain"><code>url.domainToASCII</code></a> or, more generally, the 176<a href="url.html#url_the_whatwg_url_api">WHATWG URL API</a>.</p> 177<p>The <code>punycode</code> module is a bundled version of the <a href="https://github.com/bestiejs/punycode.js">Punycode.js</a> module. It 178can be accessed using:</p> 179<pre><code class="language-js"><span class="hljs-keyword">const</span> punycode = <span class="hljs-built_in">require</span>(<span class="hljs-string">'punycode'</span>);</code></pre> 180<p><a href="https://tools.ietf.org/html/rfc3492">Punycode</a> is a character encoding scheme defined by RFC 3492 that is 181primarily intended for use in Internationalized Domain Names. Because host 182names in URLs are limited to ASCII characters only, Domain Names that contain 183non-ASCII characters must be converted into ASCII using the Punycode scheme. 184For instance, the Japanese character that translates into the English word, 185<code>'example'</code> is <code>'例'</code>. The Internationalized Domain Name, <code>'例.com'</code> (equivalent 186to <code>'example.com'</code>) is represented by Punycode as the ASCII string 187<code>'xn--fsq.com'</code>.</p> 188<p>The <code>punycode</code> module provides a simple implementation of the Punycode standard.</p> 189<p>The <code>punycode</code> module is a third-party dependency used by Node.js and 190made available to developers as a convenience. Fixes or other modifications to 191the module must be directed to the <a href="https://github.com/bestiejs/punycode.js">Punycode.js</a> project.</p> 192<section><h3><code>punycode.decode(string)</code><span><a class="mark" href="#punycode_punycode_decode_string" id="punycode_punycode_decode_string">#</a></span></h3> 193<div class="api_metadata"> 194<span>Added in: v0.5.1</span> 195</div> 196<ul> 197<li><code>string</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 198</ul> 199<p>The <code>punycode.decode()</code> method converts a <a href="https://tools.ietf.org/html/rfc3492">Punycode</a> string of ASCII-only 200characters to the equivalent string of Unicode codepoints.</p> 201<pre><code class="language-js">punycode.<span class="hljs-title function_">decode</span>(<span class="hljs-string">'maana-pta'</span>); <span class="hljs-comment">// 'mañana'</span> 202punycode.<span class="hljs-title function_">decode</span>(<span class="hljs-string">'--dqo34k'</span>); <span class="hljs-comment">// '☃-⌘'</span></code></pre> 203</section><section><h3><code>punycode.encode(string)</code><span><a class="mark" href="#punycode_punycode_encode_string" id="punycode_punycode_encode_string">#</a></span></h3> 204<div class="api_metadata"> 205<span>Added in: v0.5.1</span> 206</div> 207<ul> 208<li><code>string</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 209</ul> 210<p>The <code>punycode.encode()</code> method converts a string of Unicode codepoints to a 211<a href="https://tools.ietf.org/html/rfc3492">Punycode</a> string of ASCII-only characters.</p> 212<pre><code class="language-js">punycode.<span class="hljs-title function_">encode</span>(<span class="hljs-string">'mañana'</span>); <span class="hljs-comment">// 'maana-pta'</span> 213punycode.<span class="hljs-title function_">encode</span>(<span class="hljs-string">'☃-⌘'</span>); <span class="hljs-comment">// '--dqo34k'</span></code></pre> 214</section><section><h3><code>punycode.toASCII(domain)</code><span><a class="mark" href="#punycode_punycode_toascii_domain" id="punycode_punycode_toascii_domain">#</a></span></h3> 215<div class="api_metadata"> 216<span>Added in: v0.6.1</span> 217</div> 218<ul> 219<li><code>domain</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 220</ul> 221<p>The <code>punycode.toASCII()</code> method converts a Unicode string representing an 222Internationalized Domain Name to <a href="https://tools.ietf.org/html/rfc3492">Punycode</a>. Only the non-ASCII parts of the 223domain name will be converted. Calling <code>punycode.toASCII()</code> on a string that 224already only contains ASCII characters will have no effect.</p> 225<pre><code class="language-js"><span class="hljs-comment">// encode domain names</span> 226punycode.<span class="hljs-title function_">toASCII</span>(<span class="hljs-string">'mañana.com'</span>); <span class="hljs-comment">// 'xn--maana-pta.com'</span> 227punycode.<span class="hljs-title function_">toASCII</span>(<span class="hljs-string">'☃-⌘.com'</span>); <span class="hljs-comment">// 'xn----dqo34k.com'</span> 228punycode.<span class="hljs-title function_">toASCII</span>(<span class="hljs-string">'example.com'</span>); <span class="hljs-comment">// 'example.com'</span></code></pre> 229</section><section><h3><code>punycode.toUnicode(domain)</code><span><a class="mark" href="#punycode_punycode_tounicode_domain" id="punycode_punycode_tounicode_domain">#</a></span></h3> 230<div class="api_metadata"> 231<span>Added in: v0.6.1</span> 232</div> 233<ul> 234<li><code>domain</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 235</ul> 236<p>The <code>punycode.toUnicode()</code> method converts a string representing a domain name 237containing <a href="https://tools.ietf.org/html/rfc3492">Punycode</a> encoded characters into Unicode. Only the <a href="https://tools.ietf.org/html/rfc3492">Punycode</a> 238encoded parts of the domain name are be converted.</p> 239<pre><code class="language-js"><span class="hljs-comment">// decode domain names</span> 240punycode.<span class="hljs-title function_">toUnicode</span>(<span class="hljs-string">'xn--maana-pta.com'</span>); <span class="hljs-comment">// 'mañana.com'</span> 241punycode.<span class="hljs-title function_">toUnicode</span>(<span class="hljs-string">'xn----dqo34k.com'</span>); <span class="hljs-comment">// '☃-⌘.com'</span> 242punycode.<span class="hljs-title function_">toUnicode</span>(<span class="hljs-string">'example.com'</span>); <span class="hljs-comment">// 'example.com'</span></code></pre> 243</section><section><h3><code>punycode.ucs2</code><span><a class="mark" href="#punycode_punycode_ucs2" id="punycode_punycode_ucs2">#</a></span></h3> 244<div class="api_metadata"> 245<span>Added in: v0.7.0</span> 246</div> 247<h4><code>punycode.ucs2.decode(string)</code><span><a class="mark" href="#punycode_punycode_ucs2_decode_string" id="punycode_punycode_ucs2_decode_string">#</a></span></h4> 248<div class="api_metadata"> 249<span>Added in: v0.7.0</span> 250</div> 251<ul> 252<li><code>string</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 253</ul> 254<p>The <code>punycode.ucs2.decode()</code> method returns an array containing the numeric 255codepoint values of each Unicode symbol in the string.</p> 256<pre><code class="language-js">punycode.<span class="hljs-property">ucs2</span>.<span class="hljs-title function_">decode</span>(<span class="hljs-string">'abc'</span>); <span class="hljs-comment">// [0x61, 0x62, 0x63]</span> 257<span class="hljs-comment">// surrogate pair for U+1D306 tetragram for centre:</span> 258punycode.<span class="hljs-property">ucs2</span>.<span class="hljs-title function_">decode</span>(<span class="hljs-string">'\uD834\uDF06'</span>); <span class="hljs-comment">// [0x1D306]</span></code></pre> 259<h4><code>punycode.ucs2.encode(codePoints)</code><span><a class="mark" href="#punycode_punycode_ucs2_encode_codepoints" id="punycode_punycode_ucs2_encode_codepoints">#</a></span></h4> 260<div class="api_metadata"> 261<span>Added in: v0.7.0</span> 262</div> 263<ul> 264<li><code>codePoints</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><integer[]></a></li> 265</ul> 266<p>The <code>punycode.ucs2.encode()</code> method returns a string based on an array of 267numeric code point values.</p> 268<pre><code class="language-js">punycode.<span class="hljs-property">ucs2</span>.<span class="hljs-title function_">encode</span>([<span class="hljs-number">0x61</span>, <span class="hljs-number">0x62</span>, <span class="hljs-number">0x63</span>]); <span class="hljs-comment">// 'abc'</span> 269punycode.<span class="hljs-property">ucs2</span>.<span class="hljs-title function_">encode</span>([<span class="hljs-number">0x1D306</span>]); <span class="hljs-comment">// '\uD834\uDF06'</span></code></pre> 270</section><section><h3><code>punycode.version</code><span><a class="mark" href="#punycode_punycode_version" id="punycode_punycode_version">#</a></span></h3> 271<div class="api_metadata"> 272<span>Added in: v0.6.1</span> 273</div> 274<ul> 275<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 276</ul> 277<p>Returns a string identifying the current <a href="https://github.com/bestiejs/punycode.js">Punycode.js</a> version number.</p></section> 278 <!-- API END --> 279 </div> 280 </div> 281 </div> 282 <script> 283 'use strict'; 284 { 285 const kCustomPreference = 'customDarkTheme'; 286 const userSettings = sessionStorage.getItem(kCustomPreference); 287 const themeToggleButton = document.getElementById('theme-toggle-btn'); 288 if (userSettings === null && window.matchMedia) { 289 const mq = window.matchMedia('(prefers-color-scheme: dark)'); 290 if ('onchange' in mq) { 291 function mqChangeListener(e) { 292 document.body.classList.toggle('dark-mode', e.matches); 293 } 294 mq.addEventListener('change', mqChangeListener); 295 if (themeToggleButton) { 296 themeToggleButton.addEventListener('click', function() { 297 mq.removeEventListener('change', mqChangeListener); 298 }, { once: true }); 299 } 300 } 301 if (mq.matches) { 302 document.body.classList.add('dark-mode'); 303 } 304 } else if (userSettings === 'true') { 305 document.body.classList.add('dark-mode'); 306 } 307 if (themeToggleButton) { 308 themeToggleButton.hidden = false; 309 themeToggleButton.addEventListener('click', function() { 310 sessionStorage.setItem( 311 kCustomPreference, 312 document.body.classList.toggle('dark-mode') 313 ); 314 }); 315 } 316 } 317 </script> 318</body> 319</html> 320