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<div id="column1" data-id="module" class="interior"> 90 <header> 91 <div class="header-container"> 92 <h1>Node.js v14.20.1 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-v15.x/api/module.html">15.x</a></li> 123<li><a href="https://nodejs.org/docs/latest-v14.x/api/module.html">14.x <b>LTS</b></a></li> 124<li><a href="https://nodejs.org/docs/latest-v13.x/api/module.html">13.x</a></li> 125<li><a href="https://nodejs.org/docs/latest-v12.x/api/module.html">12.x <b>LTS</b></a></li></ol> 126 </li> 127 128 <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/master/doc/api/module.md">Edit on GitHub</a></li> 129 </ul> 130 </div> 131 <hr> 132 </header> 133 134 <details id="toc" open><summary>Table of contents</summary><ul> 135<li><a href="#module_modules_module_api">Modules: <code>module</code> API</a> 136<ul> 137<li><a href="#module_the_module_object">The <code>Module</code> object</a> 138<ul> 139<li><a href="#module_module_builtinmodules"><code>module.builtinModules</code></a></li> 140<li><a href="#module_module_createrequire_filename"><code>module.createRequire(filename)</code></a></li> 141<li><span class="stability_0"><a href="#module_module_createrequirefrompath_filename"><code>module.createRequireFromPath(filename)</code></a></span></li> 142<li><a href="#module_module_syncbuiltinesmexports"><code>module.syncBuiltinESMExports()</code></a></li> 143</ul> 144</li> 145<li><span class="stability_1"><a href="#module_source_map_v3_support">Source map v3 support</a></span> 146<ul> 147<li><a href="#module_module_findsourcemap_path"><code>module.findSourceMap(path)</code></a></li> 148<li><a href="#module_class_module_sourcemap">Class: <code>module.SourceMap</code></a> 149<ul> 150<li><a href="#module_new_sourcemap_payload"><code>new SourceMap(payload)</code></a></li> 151<li><a href="#module_sourcemap_payload"><code>sourceMap.payload</code></a></li> 152<li><a href="#module_sourcemap_findentry_linenumber_columnnumber"><code>sourceMap.findEntry(lineNumber, columnNumber)</code></a></li> 153</ul> 154</li> 155</ul> 156</li> 157</ul> 158</li> 159</ul></details> 160 161 <div id="apicontent"> 162 <h2>Modules: <code>module</code> API<span><a class="mark" href="#module_modules_module_api" id="module_modules_module_api">#</a></span></h2> 163 164<div class="api_metadata"> 165<span>Added in: v0.3.7</span> 166</div> 167<section><h3>The <code>Module</code> object<span><a class="mark" href="#module_the_module_object" id="module_the_module_object">#</a></span></h3> 168<ul> 169<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 170</ul> 171<p>Provides general utility methods when interacting with instances of 172<code>Module</code>, the <a href="modules.html#modules_the_module_object"><code>module</code></a> variable often seen in <a href="modules.html">CommonJS</a> modules. Accessed 173via <code>import 'module'</code> or <code>require('module')</code>.</p> 174<h4><code>module.builtinModules</code><span><a class="mark" href="#module_module_builtinmodules" id="module_module_builtinmodules">#</a></span></h4> 175<div class="api_metadata"> 176<span>Added in: v9.3.0, v8.10.0, v6.13.0</span> 177</div> 178<ul> 179<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a></li> 180</ul> 181<p>A list of the names of all modules provided by Node.js. Can be used to verify 182if a module is maintained by a third party or not.</p> 183<p><code>module</code> in this context isn't the same object that's provided 184by the <a href="modules.html#modules_the_module_wrapper">module wrapper</a>. To access it, require the <code>Module</code> module:</p> 185 186<pre><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-comment">// module.mjs</span> 187<span class="hljs-comment">// In an ECMAScript module</span> 188<span class="hljs-keyword">import</span> { builtinModules <span class="hljs-keyword">as</span> builtin } <span class="hljs-keyword">from</span> <span class="hljs-string">'module'</span>;</code><code class="language-js cjs"><span class="hljs-comment">// module.cjs</span> 189<span class="hljs-comment">// In a CommonJS module</span> 190<span class="hljs-keyword">const</span> builtin = <span class="hljs-built_in">require</span>(<span class="hljs-string">'module'</span>).<span class="hljs-property">builtinModules</span>;</code></pre> 191<h4><code>module.createRequire(filename)</code><span><a class="mark" href="#module_module_createrequire_filename" id="module_module_createrequire_filename">#</a></span></h4> 192<div class="api_metadata"> 193<span>Added in: v12.2.0</span> 194</div> 195<ul> 196<li><code>filename</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> | <a href="url.html#url_the_whatwg_url_api" class="type"><URL></a> Filename to be used to construct the require 197function. Must be a file URL object, file URL string, or absolute path 198string.</li> 199<li>Returns: <a href="modules.html#modules_require_id" class="type"><require></a> Require function</li> 200</ul> 201<pre><code class="language-js mjs"><span class="hljs-keyword">import</span> { createRequire } <span class="hljs-keyword">from</span> <span class="hljs-string">'module'</span>; 202<span class="hljs-keyword">const</span> <span class="hljs-built_in">require</span> = <span class="hljs-title function_">createRequire</span>(<span class="hljs-keyword">import</span>.<span class="hljs-property">meta</span>.<span class="hljs-property">url</span>); 203 204<span class="hljs-comment">// sibling-module.js is a CommonJS module.</span> 205<span class="hljs-keyword">const</span> siblingModule = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./sibling-module'</span>);</code></pre> 206<h4><code>module.createRequireFromPath(filename)</code><span><a class="mark" href="#module_module_createrequirefrompath_filename" id="module_module_createrequirefrompath_filename">#</a></span></h4> 207<div class="api_metadata"> 208<span>Added in: v10.12.0</span><span>Deprecated since: v12.2.0</span> 209</div> 210<p></p><div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated: Please use <a href="#module_module_createrequire_filename"><code>createRequire()</code></a> instead.</div><p></p> 211<ul> 212<li><code>filename</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Filename to be used to construct the relative require 213function.</li> 214<li>Returns: <a href="modules.html#modules_require_id" class="type"><require></a> Require function</li> 215</ul> 216<pre><code class="language-js"><span class="hljs-keyword">const</span> { createRequireFromPath } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'module'</span>); 217<span class="hljs-keyword">const</span> requireUtil = <span class="hljs-title function_">createRequireFromPath</span>(<span class="hljs-string">'../src/utils/'</span>); 218 219<span class="hljs-comment">// Require `../src/utils/some-tool`</span> 220requireUtil(<span class="hljs-string">'./some-tool'</span>);</code></pre> 221<h4><code>module.syncBuiltinESMExports()</code><span><a class="mark" href="#module_module_syncbuiltinesmexports" id="module_module_syncbuiltinesmexports">#</a></span></h4> 222<div class="api_metadata"> 223<span>Added in: v12.12.0</span> 224</div> 225<p>The <code>module.syncBuiltinESMExports()</code> method updates all the live bindings for 226builtin <a href="esm.html">ES Modules</a> to match the properties of the <a href="modules.html">CommonJS</a> exports. It 227does not add or remove exported names from the <a href="esm.html">ES Modules</a>.</p> 228<pre><code class="language-js"><span class="hljs-keyword">const</span> fs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>); 229<span class="hljs-keyword">const</span> assert = <span class="hljs-built_in">require</span>(<span class="hljs-string">'assert'</span>); 230<span class="hljs-keyword">const</span> { syncBuiltinESMExports } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'module'</span>); 231 232fs.<span class="hljs-property">readFile</span> = newAPI; 233 234<span class="hljs-keyword">delete</span> fs.<span class="hljs-property">readFileSync</span>; 235 236<span class="hljs-keyword">function</span> <span class="hljs-title function_">newAPI</span>(<span class="hljs-params"></span>) { 237 <span class="hljs-comment">// ...</span> 238} 239 240fs.<span class="hljs-property">newAPI</span> = newAPI; 241 242<span class="hljs-title function_">syncBuiltinESMExports</span>(); 243 244<span class="hljs-title function_">import</span>(<span class="hljs-string">'fs'</span>).<span class="hljs-title function_">then</span>(<span class="hljs-function">(<span class="hljs-params">esmFS</span>) =></span> { 245 <span class="hljs-comment">// It syncs the existing readFile property with the new value</span> 246 assert.<span class="hljs-title function_">strictEqual</span>(esmFS.<span class="hljs-property">readFile</span>, newAPI); 247 <span class="hljs-comment">// readFileSync has been deleted from the required fs</span> 248 assert.<span class="hljs-title function_">strictEqual</span>(<span class="hljs-string">'readFileSync'</span> <span class="hljs-keyword">in</span> fs, <span class="hljs-literal">false</span>); 249 <span class="hljs-comment">// syncBuiltinESMExports() does not remove readFileSync from esmFS</span> 250 assert.<span class="hljs-title function_">strictEqual</span>(<span class="hljs-string">'readFileSync'</span> <span class="hljs-keyword">in</span> esmFS, <span class="hljs-literal">true</span>); 251 <span class="hljs-comment">// syncBuiltinESMExports() does not add names</span> 252 assert.<span class="hljs-title function_">strictEqual</span>(esmFS.<span class="hljs-property">newAPI</span>, <span class="hljs-literal">undefined</span>); 253});</code></pre> 254</section><section><h3>Source map v3 support<span><a class="mark" href="#module_source_map_v3_support" id="module_source_map_v3_support">#</a></span></h3> 255<div class="api_metadata"> 256<span>Added in: v13.7.0, v12.17.0</span> 257</div> 258<p></p><div class="api_stability api_stability_1"><a href="documentation.html#documentation_stability_index">Stability: 1</a> - Experimental</div><p></p> 259<p>Helpers for interacting with the source map cache. This cache is 260populated when source map parsing is enabled and 261<a href="https://sourcemaps.info/spec.html#h.lmz475t4mvbx">source map include directives</a> are found in a modules' footer.</p> 262<p>To enable source map parsing, Node.js must be run with the flag 263<a href="cli.html#cli_enable_source_maps"><code>--enable-source-maps</code></a>, or with code coverage enabled by setting 264<a href="cli.html#cli_node_v8_coverage_dir"><code>NODE_V8_COVERAGE=dir</code></a>.</p> 265 266<pre><input class="js-flavor-selector" type="checkbox" checked aria-label="Show modern ES modules syntax"><code class="language-js mjs"><span class="hljs-comment">// module.mjs</span> 267<span class="hljs-comment">// In an ECMAScript module</span> 268<span class="hljs-keyword">import</span> { findSourceMap, <span class="hljs-title class_">SourceMap</span> } <span class="hljs-keyword">from</span> <span class="hljs-string">'module'</span>;</code><code class="language-js cjs"><span class="hljs-comment">// module.cjs</span> 269<span class="hljs-comment">// In a CommonJS module</span> 270<span class="hljs-keyword">const</span> { findSourceMap, <span class="hljs-title class_">SourceMap</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'module'</span>);</code></pre> 271<!-- Anchors to make sure old links find a target --> 272<p><a id="module_module_findsourcemap_path_error"></a></p> 273<h4><code>module.findSourceMap(path)</code><span><a class="mark" href="#module_module_findsourcemap_path" id="module_module_findsourcemap_path">#</a></span></h4> 274<div class="api_metadata"> 275<span>Added in: v13.7.0, v12.17.0</span> 276</div> 277<ul> 278<li><code>path</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 279<li>Returns: <a href="module.html#module_class_module_sourcemap" class="type"><module.SourceMap></a></li> 280</ul> 281<p><code>path</code> is the resolved path for the file for which a corresponding source map 282should be fetched.</p> 283<h4>Class: <code>module.SourceMap</code><span><a class="mark" href="#module_class_module_sourcemap" id="module_class_module_sourcemap">#</a></span></h4> 284<div class="api_metadata"> 285<span>Added in: v13.7.0, v12.17.0</span> 286</div> 287<h5><code>new SourceMap(payload)</code><span><a class="mark" href="#module_new_sourcemap_payload" id="module_new_sourcemap_payload">#</a></span></h5> 288<ul> 289<li><code>payload</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 290</ul> 291<p>Creates a new <code>sourceMap</code> instance.</p> 292<p><code>payload</code> is an object with keys matching the <a href="https://sourcemaps.info/spec.html#h.mofvlxcwqzej">Source map v3 format</a>:</p> 293<ul> 294<li><code>file</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 295<li><code>version</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 296<li><code>sources</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a></li> 297<li><code>sourcesContent</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a></li> 298<li><code>names</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a></li> 299<li><code>mappings</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 300<li><code>sourceRoot</code>: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 301</ul> 302<h5><code>sourceMap.payload</code><span><a class="mark" href="#module_sourcemap_payload" id="module_sourcemap_payload">#</a></span></h5> 303<ul> 304<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 305</ul> 306<p>Getter for the payload used to construct the <a href="#module_class_module_sourcemap"><code>SourceMap</code></a> instance.</p> 307<h5><code>sourceMap.findEntry(lineNumber, columnNumber)</code><span><a class="mark" href="#module_sourcemap_findentry_linenumber_columnnumber" id="module_sourcemap_findentry_linenumber_columnnumber">#</a></span></h5> 308<ul> 309<li><code>lineNumber</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 310<li><code>columnNumber</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 311<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 312</ul> 313<p>Given a line number and column number in the generated source file, returns 314an object representing the position in the original file. The object returned 315consists of the following keys:</p> 316<ul> 317<li>generatedLine: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 318<li>generatedColumn: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 319<li>originalSource: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 320<li>originalLine: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 321<li>originalColumn: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type"><number></a></li> 322<li>name: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 323</ul></section> 324 <!-- API END --> 325 </div> 326 </div> 327 </div> 328 <script> 329 'use strict'; 330 { 331 const kCustomPreference = 'customDarkTheme'; 332 const userSettings = sessionStorage.getItem(kCustomPreference); 333 const themeToggleButton = document.getElementById('theme-toggle-btn'); 334 if (userSettings === null && window.matchMedia) { 335 const mq = window.matchMedia('(prefers-color-scheme: dark)'); 336 if ('onchange' in mq) { 337 function mqChangeListener(e) { 338 document.body.classList.toggle('dark-mode', e.matches); 339 } 340 mq.addEventListener('change', mqChangeListener); 341 if (themeToggleButton) { 342 themeToggleButton.addEventListener('click', function() { 343 mq.removeEventListener('change', mqChangeListener); 344 }, { once: true }); 345 } 346 } 347 if (mq.matches) { 348 document.body.classList.add('dark-mode'); 349 } 350 } else if (userSettings === 'true') { 351 document.body.classList.add('dark-mode'); 352 } 353 if (themeToggleButton) { 354 themeToggleButton.hidden = false; 355 themeToggleButton.addEventListener('click', function() { 356 sessionStorage.setItem( 357 kCustomPreference, 358 document.body.classList.toggle('dark-mode') 359 ); 360 }); 361 } 362 } 363 </script> 364</body> 365</html> 366