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class="pinned-header">Node.js v18.20.1</li> 115 116 <li class="picker-header"> 117 <a href="#"> 118 <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 119 Table of contents 120 </a> 121 122 <div class="picker"><div class="toc"><ul> 123<li><span class="stability_2"><a href="#modules-commonjs-modules">Modules: CommonJS modules</a></span> 124<ul> 125<li><a href="#enabling">Enabling</a></li> 126<li><a href="#accessing-the-main-module">Accessing the main module</a></li> 127<li><a href="#package-manager-tips">Package manager tips</a></li> 128<li><a href="#the-mjs-extension">The <code>.mjs</code> extension</a></li> 129<li><a href="#all-together">All together</a></li> 130<li><a href="#caching">Caching</a> 131<ul> 132<li><a href="#module-caching-caveats">Module caching caveats</a></li> 133</ul> 134</li> 135<li><a href="#core-modules">Core modules</a></li> 136<li><a href="#cycles">Cycles</a></li> 137<li><a href="#file-modules">File modules</a></li> 138<li><span class="stability_3"><a href="#folders-as-modules">Folders as modules</a></span></li> 139<li><a href="#loading-from-node_modules-folders">Loading from <code>node_modules</code> folders</a></li> 140<li><a href="#loading-from-the-global-folders">Loading from the global folders</a></li> 141<li><a href="#the-module-wrapper">The module wrapper</a></li> 142<li><a href="#the-module-scope">The module scope</a> 143<ul> 144<li><a href="#__dirname"><code>__dirname</code></a></li> 145<li><a href="#__filename"><code>__filename</code></a></li> 146<li><a href="#exports"><code>exports</code></a></li> 147<li><a href="#module"><code>module</code></a></li> 148<li><a href="#requireid"><code>require(id)</code></a> 149<ul> 150<li><a href="#requirecache"><code>require.cache</code></a></li> 151<li><span class="stability_0"><a href="#requireextensions"><code>require.extensions</code></a></span></li> 152<li><a href="#requiremain"><code>require.main</code></a></li> 153<li><a href="#requireresolverequest-options"><code>require.resolve(request[, options])</code></a> 154<ul> 155<li><a href="#requireresolvepathsrequest"><code>require.resolve.paths(request)</code></a></li> 156</ul> 157</li> 158</ul> 159</li> 160</ul> 161</li> 162<li><a href="#the-module-object">The <code>module</code> object</a> 163<ul> 164<li><a href="#modulechildren"><code>module.children</code></a></li> 165<li><a href="#moduleexports"><code>module.exports</code></a> 166<ul> 167<li><a href="#exports-shortcut"><code>exports</code> shortcut</a></li> 168</ul> 169</li> 170<li><a href="#modulefilename"><code>module.filename</code></a></li> 171<li><a href="#moduleid"><code>module.id</code></a></li> 172<li><a href="#moduleispreloading"><code>module.isPreloading</code></a></li> 173<li><a href="#moduleloaded"><code>module.loaded</code></a></li> 174<li><span class="stability_0"><a href="#moduleparent"><code>module.parent</code></a></span></li> 175<li><a href="#modulepath"><code>module.path</code></a></li> 176<li><a href="#modulepaths"><code>module.paths</code></a></li> 177<li><a href="#modulerequireid"><code>module.require(id)</code></a></li> 178</ul> 179</li> 180<li><a href="#the-module-object_1">The <code>Module</code> object</a></li> 181<li><a href="#source-map-v3-support">Source map v3 support</a></li> 182</ul> 183</li> 184</ul></div></div> 185 </li> 186 187 188 <li class="picker-header"> 189 <a href="#"> 190 <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 191 Index 192 </a> 193 194 <div class="picker"><ul> 195<li><a href="documentation.html" class="nav-documentation">About this documentation</a></li> 196<li><a href="synopsis.html" class="nav-synopsis">Usage and example</a></li> 197 198 <li> 199 <a href="index.html">Index</a> 200 </li> 201 </ul> 202 203<hr class="line"> 204<ul> 205<li><a href="assert.html" class="nav-assert">Assertion testing</a></li> 206<li><a href="async_context.html" class="nav-async_context">Asynchronous context tracking</a></li> 207<li><a href="async_hooks.html" class="nav-async_hooks">Async hooks</a></li> 208<li><a href="buffer.html" class="nav-buffer">Buffer</a></li> 209<li><a href="addons.html" class="nav-addons">C++ addons</a></li> 210<li><a href="n-api.html" class="nav-n-api">C/C++ addons with Node-API</a></li> 211<li><a href="embedding.html" class="nav-embedding">C++ embedder API</a></li> 212<li><a href="child_process.html" class="nav-child_process">Child processes</a></li> 213<li><a href="cluster.html" class="nav-cluster">Cluster</a></li> 214<li><a href="cli.html" class="nav-cli">Command-line options</a></li> 215<li><a href="console.html" class="nav-console">Console</a></li> 216<li><a href="corepack.html" class="nav-corepack">Corepack</a></li> 217<li><a href="crypto.html" class="nav-crypto">Crypto</a></li> 218<li><a href="debugger.html" class="nav-debugger">Debugger</a></li> 219<li><a href="deprecations.html" 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class="nav-single-executable-applications">Single executable applications</a></li> 248<li><a href="stream.html" class="nav-stream">Stream</a></li> 249<li><a href="string_decoder.html" class="nav-string_decoder">String decoder</a></li> 250<li><a href="test.html" class="nav-test">Test runner</a></li> 251<li><a href="timers.html" class="nav-timers">Timers</a></li> 252<li><a href="tls.html" class="nav-tls">TLS/SSL</a></li> 253<li><a href="tracing.html" class="nav-tracing">Trace events</a></li> 254<li><a href="tty.html" class="nav-tty">TTY</a></li> 255<li><a href="dgram.html" class="nav-dgram">UDP/datagram</a></li> 256<li><a href="url.html" class="nav-url">URL</a></li> 257<li><a href="util.html" class="nav-util">Utilities</a></li> 258<li><a href="v8.html" class="nav-v8">V8</a></li> 259<li><a href="vm.html" class="nav-vm">VM</a></li> 260<li><a href="wasi.html" class="nav-wasi">WASI</a></li> 261<li><a href="webcrypto.html" class="nav-webcrypto">Web Crypto API</a></li> 262<li><a 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href="https://nodejs.org/docs/latest-v17.x/api/modules.html">17.x</a></li> 283<li><a href="https://nodejs.org/docs/latest-v16.x/api/modules.html">16.x</a></li> 284<li><a href="https://nodejs.org/docs/latest-v15.x/api/modules.html">15.x</a></li> 285<li><a href="https://nodejs.org/docs/latest-v14.x/api/modules.html">14.x</a></li> 286<li><a href="https://nodejs.org/docs/latest-v13.x/api/modules.html">13.x</a></li> 287<li><a href="https://nodejs.org/docs/latest-v12.x/api/modules.html">12.x</a></li> 288<li><a href="https://nodejs.org/docs/latest-v11.x/api/modules.html">11.x</a></li> 289<li><a href="https://nodejs.org/docs/latest-v10.x/api/modules.html">10.x</a></li> 290<li><a href="https://nodejs.org/docs/latest-v9.x/api/modules.html">9.x</a></li> 291<li><a href="https://nodejs.org/docs/latest-v8.x/api/modules.html">8.x</a></li> 292<li><a href="https://nodejs.org/docs/latest-v7.x/api/modules.html">7.x</a></li> 293<li><a href="https://nodejs.org/docs/latest-v6.x/api/modules.html">6.x</a></li> 294<li><a href="https://nodejs.org/docs/latest-v5.x/api/modules.html">5.x</a></li> 295<li><a href="https://nodejs.org/docs/latest-v4.x/api/modules.html">4.x</a></li> 296<li><a href="https://nodejs.org/docs/latest-v0.12.x/api/modules.html">0.12.x</a></li> 297<li><a href="https://nodejs.org/docs/latest-v0.10.x/api/modules.html">0.10.x</a></li></ol></div> 298 </li> 299 300 <li class="picker-header"> 301 <a href="#"> 302 <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 303 Options 304 </a> 305 306 <div class="picker"> 307 <ul> 308 <li> 309 <a href="all.html">View on single page</a> 310 </li> 311 <li> 312 <a href="modules.json">View as JSON</a> 313 </li> 314 <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/main/doc/api/modules.md">Edit on GitHub</a></li> 315 </ul> 316 </div> 317 </li> 318 </ul> 319 </div> 320 <hr> 321 </header> 322 323 <details id="toc" open><summary>Table of contents</summary><ul> 324<li><span class="stability_2"><a href="#modules-commonjs-modules">Modules: CommonJS modules</a></span> 325<ul> 326<li><a href="#enabling">Enabling</a></li> 327<li><a href="#accessing-the-main-module">Accessing the main module</a></li> 328<li><a href="#package-manager-tips">Package manager tips</a></li> 329<li><a href="#the-mjs-extension">The <code>.mjs</code> extension</a></li> 330<li><a href="#all-together">All together</a></li> 331<li><a href="#caching">Caching</a> 332<ul> 333<li><a href="#module-caching-caveats">Module caching caveats</a></li> 334</ul> 335</li> 336<li><a href="#core-modules">Core modules</a></li> 337<li><a href="#cycles">Cycles</a></li> 338<li><a href="#file-modules">File modules</a></li> 339<li><span class="stability_3"><a href="#folders-as-modules">Folders as modules</a></span></li> 340<li><a href="#loading-from-node_modules-folders">Loading from <code>node_modules</code> folders</a></li> 341<li><a href="#loading-from-the-global-folders">Loading from the global folders</a></li> 342<li><a href="#the-module-wrapper">The module wrapper</a></li> 343<li><a href="#the-module-scope">The module scope</a> 344<ul> 345<li><a href="#__dirname"><code>__dirname</code></a></li> 346<li><a href="#__filename"><code>__filename</code></a></li> 347<li><a href="#exports"><code>exports</code></a></li> 348<li><a href="#module"><code>module</code></a></li> 349<li><a href="#requireid"><code>require(id)</code></a> 350<ul> 351<li><a href="#requirecache"><code>require.cache</code></a></li> 352<li><span class="stability_0"><a href="#requireextensions"><code>require.extensions</code></a></span></li> 353<li><a href="#requiremain"><code>require.main</code></a></li> 354<li><a href="#requireresolverequest-options"><code>require.resolve(request[, options])</code></a> 355<ul> 356<li><a href="#requireresolvepathsrequest"><code>require.resolve.paths(request)</code></a></li> 357</ul> 358</li> 359</ul> 360</li> 361</ul> 362</li> 363<li><a href="#the-module-object">The <code>module</code> object</a> 364<ul> 365<li><a href="#modulechildren"><code>module.children</code></a></li> 366<li><a href="#moduleexports"><code>module.exports</code></a> 367<ul> 368<li><a href="#exports-shortcut"><code>exports</code> shortcut</a></li> 369</ul> 370</li> 371<li><a href="#modulefilename"><code>module.filename</code></a></li> 372<li><a href="#moduleid"><code>module.id</code></a></li> 373<li><a href="#moduleispreloading"><code>module.isPreloading</code></a></li> 374<li><a href="#moduleloaded"><code>module.loaded</code></a></li> 375<li><span class="stability_0"><a href="#moduleparent"><code>module.parent</code></a></span></li> 376<li><a href="#modulepath"><code>module.path</code></a></li> 377<li><a href="#modulepaths"><code>module.paths</code></a></li> 378<li><a href="#modulerequireid"><code>module.require(id)</code></a></li> 379</ul> 380</li> 381<li><a href="#the-module-object_1">The <code>Module</code> object</a></li> 382<li><a href="#source-map-v3-support">Source map v3 support</a></li> 383</ul> 384</li> 385</ul></details> 386 387 <div id="apicontent"> 388 <h2>Modules: CommonJS modules<span><a class="mark" href="#modules-commonjs-modules" id="modules-commonjs-modules">#</a></span><a aria-hidden="true" class="legacy" id="modules_modules_commonjs_modules"></a></h2> 389 390<p></p><div class="api_stability api_stability_2"><a href="documentation.html#stability-index">Stability: 2</a> - Stable</div><p></p> 391 392<p>CommonJS modules are the original way to package JavaScript code for Node.js. 393Node.js also supports the <a href="esm.html">ECMAScript modules</a> standard used by browsers 394and other JavaScript runtimes.</p> 395<p>In Node.js, each file is treated as a separate module. For 396example, consider a file named <code>foo.js</code>:</p> 397<pre><code class="language-js"><span class="hljs-keyword">const</span> circle = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./circle.js'</span>); 398<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`The area of a circle of radius 4 is <span class="hljs-subst">${circle.area(<span class="hljs-number">4</span>)}</span>`</span>);</code> <button class="copy-button">copy</button></pre> 399<p>On the first line, <code>foo.js</code> loads the module <code>circle.js</code> that is in the same 400directory as <code>foo.js</code>.</p> 401<p>Here are the contents of <code>circle.js</code>:</p> 402<pre><code class="language-js"><span class="hljs-keyword">const</span> { <span class="hljs-variable constant_">PI</span> } = <span class="hljs-title class_">Math</span>; 403 404<span class="hljs-built_in">exports</span>.<span class="hljs-property">area</span> = <span class="hljs-function">(<span class="hljs-params">r</span>) =></span> <span class="hljs-variable constant_">PI</span> * r ** <span class="hljs-number">2</span>; 405 406<span class="hljs-built_in">exports</span>.<span class="hljs-property">circumference</span> = <span class="hljs-function">(<span class="hljs-params">r</span>) =></span> <span class="hljs-number">2</span> * <span class="hljs-variable constant_">PI</span> * r;</code> <button class="copy-button">copy</button></pre> 407<p>The module <code>circle.js</code> has exported the functions <code>area()</code> and 408<code>circumference()</code>. Functions and objects are added to the root of a module 409by specifying additional properties on the special <code>exports</code> object.</p> 410<p>Variables local to the module will be private, because the module is wrapped 411in a function by Node.js (see <a href="#the-module-wrapper">module wrapper</a>). 412In this example, the variable <code>PI</code> is private to <code>circle.js</code>.</p> 413<p>The <code>module.exports</code> property can be assigned a new value (such as a function 414or object).</p> 415<p>Below, <code>bar.js</code> makes use of the <code>square</code> module, which exports a Square class:</p> 416<pre><code class="language-js"><span class="hljs-keyword">const</span> <span class="hljs-title class_">Square</span> = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./square.js'</span>); 417<span class="hljs-keyword">const</span> mySquare = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Square</span>(<span class="hljs-number">2</span>); 418<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`The area of mySquare is <span class="hljs-subst">${mySquare.area()}</span>`</span>);</code> <button class="copy-button">copy</button></pre> 419<p>The <code>square</code> module is defined in <code>square.js</code>:</p> 420<pre><code class="language-js"><span class="hljs-comment">// Assigning to exports will not modify module, must use module.exports</span> 421<span class="hljs-variable language_">module</span>.<span class="hljs-property">exports</span> = <span class="hljs-keyword">class</span> <span class="hljs-title class_">Square</span> { 422 <span class="hljs-title function_">constructor</span>(<span class="hljs-params">width</span>) { 423 <span class="hljs-variable language_">this</span>.<span class="hljs-property">width</span> = width; 424 } 425 426 <span class="hljs-title function_">area</span>(<span class="hljs-params"></span>) { 427 <span class="hljs-keyword">return</span> <span class="hljs-variable language_">this</span>.<span class="hljs-property">width</span> ** <span class="hljs-number">2</span>; 428 } 429};</code> <button class="copy-button">copy</button></pre> 430<p>The CommonJS module system is implemented in the <a href="module.html"><code>module</code> core module</a>.</p> 431<section><h3>Enabling<span><a class="mark" href="#enabling" id="enabling">#</a></span><a aria-hidden="true" class="legacy" id="modules_enabling"></a></h3> 432 433<p>Node.js has two module systems: CommonJS modules and <a href="esm.html">ECMAScript modules</a>.</p> 434<p>By default, Node.js will treat the following as CommonJS modules:</p> 435<ul> 436<li> 437<p>Files with a <code>.cjs</code> extension;</p> 438</li> 439<li> 440<p>Files with a <code>.js</code> extension when the nearest parent <code>package.json</code> file 441contains a top-level field <a href="packages.html#type"><code>"type"</code></a> with a value of <code>"commonjs"</code>.</p> 442</li> 443<li> 444<p>Files with a <code>.js</code> extension when the nearest parent <code>package.json</code> file 445doesn't contain a top-level field <a href="packages.html#type"><code>"type"</code></a>. Package authors should include 446the <a href="packages.html#type"><code>"type"</code></a> field, even in packages where all sources are CommonJS. Being 447explicit about the <code>type</code> of the package will make things easier for build 448tools and loaders to determine how the files in the package should be 449interpreted.</p> 450</li> 451<li> 452<p>Files with an extension that is not <code>.mjs</code>, <code>.cjs</code>, <code>.json</code>, <code>.node</code>, or <code>.js</code> 453(when the nearest parent <code>package.json</code> file contains a top-level field 454<a href="packages.html#type"><code>"type"</code></a> with a value of <code>"module"</code>, those files will be recognized as 455CommonJS modules only if they are being included via <code>require()</code>, not when 456used as the command-line entry point of the program).</p> 457</li> 458</ul> 459<p>See <a href="packages.html#determining-module-system">Determining module system</a> for more details.</p> 460<p>Calling <code>require()</code> always use the CommonJS module loader. Calling <code>import()</code> 461always use the ECMAScript module loader.</p> 462</section><section><h3>Accessing the main module<span><a class="mark" href="#accessing-the-main-module" id="accessing-the-main-module">#</a></span><a aria-hidden="true" class="legacy" id="modules_accessing_the_main_module"></a></h3> 463 464<p>When a file is run directly from Node.js, <code>require.main</code> is set to its 465<code>module</code>. That means that it is possible to determine whether a file has been 466run directly by testing <code>require.main === module</code>.</p> 467<p>For a file <code>foo.js</code>, this will be <code>true</code> if run via <code>node foo.js</code>, but 468<code>false</code> if run by <code>require('./foo')</code>.</p> 469<p>When the entry point is not a CommonJS module, <code>require.main</code> is <code>undefined</code>, 470and the main module is out of reach.</p> 471</section><section><h3>Package manager tips<span><a class="mark" href="#package-manager-tips" id="package-manager-tips">#</a></span><a aria-hidden="true" class="legacy" id="modules_package_manager_tips"></a></h3> 472 473<p>The semantics of the Node.js <code>require()</code> function were designed to be general 474enough to support reasonable directory structures. Package manager programs 475such as <code>dpkg</code>, <code>rpm</code>, and <code>npm</code> will hopefully find it possible to build 476native packages from Node.js modules without modification.</p> 477<p>Below we give a suggested directory structure that could work:</p> 478<p>Let's say that we wanted to have the folder at 479<code>/usr/lib/node/<some-package>/<some-version></code> hold the contents of a 480specific version of a package.</p> 481<p>Packages can depend on one another. In order to install package <code>foo</code>, it 482may be necessary to install a specific version of package <code>bar</code>. The <code>bar</code> 483package may itself have dependencies, and in some cases, these may even collide 484or form cyclic dependencies.</p> 485<p>Because Node.js looks up the <code>realpath</code> of any modules it loads (that is, it 486resolves symlinks) and then <a href="#loading-from-node_modules-folders">looks for their dependencies in <code>node_modules</code> folders</a>, 487this situation can be resolved with the following architecture:</p> 488<ul> 489<li><code>/usr/lib/node/foo/1.2.3/</code>: Contents of the <code>foo</code> package, version 1.2.3.</li> 490<li><code>/usr/lib/node/bar/4.3.2/</code>: Contents of the <code>bar</code> package that <code>foo</code> depends 491on.</li> 492<li><code>/usr/lib/node/foo/1.2.3/node_modules/bar</code>: Symbolic link to 493<code>/usr/lib/node/bar/4.3.2/</code>.</li> 494<li><code>/usr/lib/node/bar/4.3.2/node_modules/*</code>: Symbolic links to the packages that 495<code>bar</code> depends on.</li> 496</ul> 497<p>Thus, even if a cycle is encountered, or if there are dependency 498conflicts, every module will be able to get a version of its dependency 499that it can use.</p> 500<p>When the code in the <code>foo</code> package does <code>require('bar')</code>, it will get the 501version that is symlinked into <code>/usr/lib/node/foo/1.2.3/node_modules/bar</code>. 502Then, when the code in the <code>bar</code> package calls <code>require('quux')</code>, it'll get 503the version that is symlinked into 504<code>/usr/lib/node/bar/4.3.2/node_modules/quux</code>.</p> 505<p>Furthermore, to make the module lookup process even more optimal, rather 506than putting packages directly in <code>/usr/lib/node</code>, we could put them in 507<code>/usr/lib/node_modules/<name>/<version></code>. Then Node.js will not bother 508looking for missing dependencies in <code>/usr/node_modules</code> or <code>/node_modules</code>.</p> 509<p>In order to make modules available to the Node.js REPL, it might be useful to 510also add the <code>/usr/lib/node_modules</code> folder to the <code>$NODE_PATH</code> environment 511variable. Since the module lookups using <code>node_modules</code> folders are all 512relative, and based on the real path of the files making the calls to 513<code>require()</code>, the packages themselves can be anywhere.</p> 514</section><section><h3>The <code>.mjs</code> extension<span><a class="mark" href="#the-mjs-extension" id="the-mjs-extension">#</a></span><a aria-hidden="true" class="legacy" id="modules_the_mjs_extension"></a></h3> 515<p>Due to the synchronous nature of <code>require()</code>, it is not possible to use it to 516load ECMAScript module files. Attempting to do so will throw a 517<a href="errors.html#err_require_esm"><code>ERR_REQUIRE_ESM</code></a> error. Use <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/import"><code>import()</code></a> instead.</p> 518<p>The <code>.mjs</code> extension is reserved for <a href="esm.html">ECMAScript Modules</a> which cannot be 519loaded via <code>require()</code>. See <a href="packages.html#determining-module-system">Determining module system</a> section for more info 520regarding which files are parsed as ECMAScript modules.</p> 521</section><section><h3>All together<span><a class="mark" href="#all-together" id="all-together">#</a></span><a aria-hidden="true" class="legacy" id="modules_all_together"></a></h3> 522 523<p>To get the exact filename that will be loaded when <code>require()</code> is called, use 524the <code>require.resolve()</code> function.</p> 525<p>Putting together all of the above, here is the high-level algorithm 526in pseudocode of what <code>require()</code> does:</p> 527<pre>require(X) from module at path Y 5281. If X is a core module, 529 a. return the core module 530 b. STOP 5312. If X begins with '/' 532 a. set Y to be the file system root 5333. If X begins with './' or '/' or '../' 534 a. LOAD_AS_FILE(Y + X) 535 b. LOAD_AS_DIRECTORY(Y + X) 536 c. THROW "not found" 5374. If X begins with '#' 538 a. LOAD_PACKAGE_IMPORTS(X, dirname(Y)) 5395. LOAD_PACKAGE_SELF(X, dirname(Y)) 5406. LOAD_NODE_MODULES(X, dirname(Y)) 5417. THROW "not found" 542 543LOAD_AS_FILE(X) 5441. If X is a file, load X as its file extension format. STOP 5452. If X.js is a file, load X.js as JavaScript text. STOP 5463. If X.json is a file, parse X.json to a JavaScript Object. STOP 5474. If X.node is a file, load X.node as binary addon. STOP 548 549LOAD_INDEX(X) 5501. If X/index.js is a file, load X/index.js as JavaScript text. STOP 5512. If X/index.json is a file, parse X/index.json to a JavaScript object. STOP 5523. If X/index.node is a file, load X/index.node as binary addon. STOP 553 554LOAD_AS_DIRECTORY(X) 5551. If X/package.json is a file, 556 a. Parse X/package.json, and look for "main" field. 557 b. If "main" is a falsy value, GOTO 2. 558 c. let M = X + (json main field) 559 d. LOAD_AS_FILE(M) 560 e. LOAD_INDEX(M) 561 f. LOAD_INDEX(X) DEPRECATED 562 g. THROW "not found" 5632. LOAD_INDEX(X) 564 565LOAD_NODE_MODULES(X, START) 5661. let DIRS = NODE_MODULES_PATHS(START) 5672. for each DIR in DIRS: 568 a. LOAD_PACKAGE_EXPORTS(X, DIR) 569 b. LOAD_AS_FILE(DIR/X) 570 c. LOAD_AS_DIRECTORY(DIR/X) 571 572NODE_MODULES_PATHS(START) 5731. let PARTS = path split(START) 5742. let I = count of PARTS - 1 5753. let DIRS = [] 5764. while I >= 0, 577 a. if PARTS[I] = "node_modules" CONTINUE 578 b. DIR = path join(PARTS[0 .. I] + "node_modules") 579 c. DIRS = DIR + DIRS 580 d. let I = I - 1 5815. return DIRS + GLOBAL_FOLDERS 582 583LOAD_PACKAGE_IMPORTS(X, DIR) 5841. Find the closest package scope SCOPE to DIR. 5852. If no scope was found, return. 5863. If the SCOPE/package.json "imports" is null or undefined, return. 5874. let MATCH = PACKAGE_IMPORTS_RESOLVE(X, pathToFileURL(SCOPE), 588 ["node", "require"]) <a href="esm.md#resolver-algorithm-specification">defined in the ESM resolver</a>. 5895. RESOLVE_ESM_MATCH(MATCH). 590 591LOAD_PACKAGE_EXPORTS(X, DIR) 5921. Try to interpret X as a combination of NAME and SUBPATH where the name 593 may have a @scope/ prefix and the subpath begins with a slash (`/`). 5942. If X does not match this pattern or DIR/NAME/package.json is not a file, 595 return. 5963. Parse DIR/NAME/package.json, and look for "exports" field. 5974. If "exports" is null or undefined, return. 5985. let MATCH = PACKAGE_EXPORTS_RESOLVE(pathToFileURL(DIR/NAME), "." + SUBPATH, 599 `package.json` "exports", ["node", "require"]) <a href="esm.md#resolver-algorithm-specification">defined in the ESM resolver</a>. 6006. RESOLVE_ESM_MATCH(MATCH) 601 602LOAD_PACKAGE_SELF(X, DIR) 6031. Find the closest package scope SCOPE to DIR. 6042. If no scope was found, return. 6053. If the SCOPE/package.json "exports" is null or undefined, return. 6064. If the SCOPE/package.json "name" is not the first segment of X, return. 6075. let MATCH = PACKAGE_EXPORTS_RESOLVE(pathToFileURL(SCOPE), 608 "." + X.slice("name".length), `package.json` "exports", ["node", "require"]) 609 <a href="esm.md#resolver-algorithm-specification">defined in the ESM resolver</a>. 6106. RESOLVE_ESM_MATCH(MATCH) 611 612RESOLVE_ESM_MATCH(MATCH) 6131. let RESOLVED_PATH = fileURLToPath(MATCH) 6142. If the file at RESOLVED_PATH exists, load RESOLVED_PATH as its extension 615 format. STOP 6163. THROW "not found" 617</pre> 618</section><section><h3>Caching<span><a class="mark" href="#caching" id="caching">#</a></span><a aria-hidden="true" class="legacy" id="modules_caching"></a></h3> 619 620<p>Modules are cached after the first time they are loaded. This means (among other 621things) that every call to <code>require('foo')</code> will get exactly the same object 622returned, if it would resolve to the same file.</p> 623<p>Provided <code>require.cache</code> is not modified, multiple calls to <code>require('foo')</code> 624will not cause the module code to be executed multiple times. This is an 625important feature. With it, "partially done" objects can be returned, thus 626allowing transitive dependencies to be loaded even when they would cause cycles.</p> 627<p>To have a module execute code multiple times, export a function, and call that 628function.</p> 629<h4>Module caching caveats<span><a class="mark" href="#module-caching-caveats" id="module-caching-caveats">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_caching_caveats"></a></h4> 630 631<p>Modules are cached based on their resolved filename. Since modules may resolve 632to a different filename based on the location of the calling module (loading 633from <code>node_modules</code> folders), it is not a <em>guarantee</em> that <code>require('foo')</code> will 634always return the exact same object, if it would resolve to different files.</p> 635<p>Additionally, on case-insensitive file systems or operating systems, different 636resolved filenames can point to the same file, but the cache will still treat 637them as different modules and will reload the file multiple times. For example, 638<code>require('./foo')</code> and <code>require('./FOO')</code> return two different objects, 639irrespective of whether or not <code>./foo</code> and <code>./FOO</code> are the same file.</p> 640</section><section><h3>Core modules<span><a class="mark" href="#core-modules" id="core-modules">#</a></span><a aria-hidden="true" class="legacy" id="modules_core_modules"></a></h3> 641 642<div class="api_metadata"> 643<details class="changelog"><summary>History</summary> 644<table> 645<tbody><tr><th>Version</th><th>Changes</th></tr> 646<tr><td>v16.0.0, v14.18.0</td> 647<td><p>Added <code>node:</code> import support to <code>require(...)</code>.</p></td></tr> 648</tbody></table> 649</details> 650</div> 651<p>Node.js has several modules compiled into the binary. These modules are 652described in greater detail elsewhere in this documentation.</p> 653<p>The core modules are defined within the Node.js source and are located in the 654<code>lib/</code> folder.</p> 655<p>Core modules can be identified using the <code>node:</code> prefix, in which case 656it bypasses the <code>require</code> cache. For instance, <code>require('node:http')</code> will 657always return the built in HTTP module, even if there is <code>require.cache</code> entry 658by that name.</p> 659<p>Some core modules are always preferentially loaded if their identifier is 660passed to <code>require()</code>. For instance, <code>require('http')</code> will always 661return the built-in HTTP module, even if there is a file by that name. The list 662of core modules that can be loaded without using the <code>node:</code> prefix is exposed 663as <a href="module.html#modulebuiltinmodules"><code>module.builtinModules</code></a>.</p> 664</section><section><h3>Cycles<span><a class="mark" href="#cycles" id="cycles">#</a></span><a aria-hidden="true" class="legacy" id="modules_cycles"></a></h3> 665 666<p>When there are circular <code>require()</code> calls, a module might not have finished 667executing when it is returned.</p> 668<p>Consider this situation:</p> 669<p><code>a.js</code>:</p> 670<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'a starting'</span>); 671<span class="hljs-built_in">exports</span>.<span class="hljs-property">done</span> = <span class="hljs-literal">false</span>; 672<span class="hljs-keyword">const</span> b = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./b.js'</span>); 673<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'in a, b.done = %j'</span>, b.<span class="hljs-property">done</span>); 674<span class="hljs-built_in">exports</span>.<span class="hljs-property">done</span> = <span class="hljs-literal">true</span>; 675<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'a done'</span>);</code> <button class="copy-button">copy</button></pre> 676<p><code>b.js</code>:</p> 677<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'b starting'</span>); 678<span class="hljs-built_in">exports</span>.<span class="hljs-property">done</span> = <span class="hljs-literal">false</span>; 679<span class="hljs-keyword">const</span> a = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./a.js'</span>); 680<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'in b, a.done = %j'</span>, a.<span class="hljs-property">done</span>); 681<span class="hljs-built_in">exports</span>.<span class="hljs-property">done</span> = <span class="hljs-literal">true</span>; 682<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'b done'</span>);</code> <button class="copy-button">copy</button></pre> 683<p><code>main.js</code>:</p> 684<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'main starting'</span>); 685<span class="hljs-keyword">const</span> a = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./a.js'</span>); 686<span class="hljs-keyword">const</span> b = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./b.js'</span>); 687<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'in main, a.done = %j, b.done = %j'</span>, a.<span class="hljs-property">done</span>, b.<span class="hljs-property">done</span>);</code> <button class="copy-button">copy</button></pre> 688<p>When <code>main.js</code> loads <code>a.js</code>, then <code>a.js</code> in turn loads <code>b.js</code>. At that 689point, <code>b.js</code> tries to load <code>a.js</code>. In order to prevent an infinite 690loop, an <strong>unfinished copy</strong> of the <code>a.js</code> exports object is returned to the 691<code>b.js</code> module. <code>b.js</code> then finishes loading, and its <code>exports</code> object is 692provided to the <code>a.js</code> module.</p> 693<p>By the time <code>main.js</code> has loaded both modules, they're both finished. 694The output of this program would thus be:</p> 695<pre><code class="language-console"><span class="hljs-meta prompt_">$ </span><span class="language-bash">node main.js</span> 696main starting 697a starting 698b starting 699in b, a.done = false 700b done 701in a, b.done = true 702a done 703in main, a.done = true, b.done = true</code> <button class="copy-button">copy</button></pre> 704<p>Careful planning is required to allow cyclic module dependencies to work 705correctly within an application.</p> 706</section><section><h3>File modules<span><a class="mark" href="#file-modules" id="file-modules">#</a></span><a aria-hidden="true" class="legacy" id="modules_file_modules"></a></h3> 707 708<p>If the exact filename is not found, then Node.js will attempt to load the 709required filename with the added extensions: <code>.js</code>, <code>.json</code>, and finally 710<code>.node</code>. When loading a file that has a different extension (e.g. <code>.cjs</code>), its 711full name must be passed to <code>require()</code>, including its file extension (e.g. 712<code>require('./file.cjs')</code>).</p> 713<p><code>.json</code> files are parsed as JSON text files, <code>.node</code> files are interpreted as 714compiled addon modules loaded with <code>process.dlopen()</code>. Files using any other 715extension (or no extension at all) are parsed as JavaScript text files. Refer to 716the <a href="packages.html#determining-module-system">Determining module system</a> section to understand what parse goal will be 717used.</p> 718<p>A required module prefixed with <code>'/'</code> is an absolute path to the file. For 719example, <code>require('/home/marco/foo.js')</code> will load the file at 720<code>/home/marco/foo.js</code>.</p> 721<p>A required module prefixed with <code>'./'</code> is relative to the file calling 722<code>require()</code>. That is, <code>circle.js</code> must be in the same directory as <code>foo.js</code> for 723<code>require('./circle')</code> to find it.</p> 724<p>Without a leading <code>'/'</code>, <code>'./'</code>, or <code>'../'</code> to indicate a file, the module must 725either be a core module or is loaded from a <code>node_modules</code> folder.</p> 726<p>If the given path does not exist, <code>require()</code> will throw a 727<a href="errors.html#module_not_found"><code>MODULE_NOT_FOUND</code></a> error.</p> 728</section><section><h3>Folders as modules<span><a class="mark" href="#folders-as-modules" id="folders-as-modules">#</a></span><a aria-hidden="true" class="legacy" id="modules_folders_as_modules"></a></h3> 729 730<p></p><div class="api_stability api_stability_3"><a href="documentation.html#stability-index">Stability: 3</a> - Legacy: Use <a href="packages.html#subpath-exports">subpath exports</a> or <a href="packages.html#subpath-imports">subpath imports</a> instead.</div><p></p> 731<p>There are three ways in which a folder may be passed to <code>require()</code> as 732an argument.</p> 733<p>The first is to create a <a href="packages.html#nodejs-packagejson-field-definitions"><code>package.json</code></a> file in the root of the folder, 734which specifies a <code>main</code> module. An example <a href="packages.html#nodejs-packagejson-field-definitions"><code>package.json</code></a> file might 735look like this:</p> 736<pre><code class="language-json"><span class="hljs-punctuation">{</span> <span class="hljs-attr">"name"</span> <span class="hljs-punctuation">:</span> <span class="hljs-string">"some-library"</span><span class="hljs-punctuation">,</span> 737 <span class="hljs-attr">"main"</span> <span class="hljs-punctuation">:</span> <span class="hljs-string">"./lib/some-library.js"</span> <span class="hljs-punctuation">}</span></code> <button class="copy-button">copy</button></pre> 738<p>If this was in a folder at <code>./some-library</code>, then 739<code>require('./some-library')</code> would attempt to load 740<code>./some-library/lib/some-library.js</code>.</p> 741<p>If there is no <a href="packages.html#nodejs-packagejson-field-definitions"><code>package.json</code></a> file present in the directory, or if the 742<a href="packages.html#main"><code>"main"</code></a> entry is missing or cannot be resolved, then Node.js 743will attempt to load an <code>index.js</code> or <code>index.node</code> file out of that 744directory. For example, if there was no <a href="packages.html#nodejs-packagejson-field-definitions"><code>package.json</code></a> file in the previous 745example, then <code>require('./some-library')</code> would attempt to load:</p> 746<ul> 747<li><code>./some-library/index.js</code></li> 748<li><code>./some-library/index.node</code></li> 749</ul> 750<p>If these attempts fail, then Node.js will report the entire module as missing 751with the default error:</p> 752<pre><code class="language-console">Error: Cannot find module 'some-library'</code> <button class="copy-button">copy</button></pre> 753<p>In all three above cases, an <code>import('./some-library')</code> call would result in a 754<a href="errors.html#err_unsupported_dir_import"><code>ERR_UNSUPPORTED_DIR_IMPORT</code></a> error. Using package <a href="packages.html#subpath-exports">subpath exports</a> or 755<a href="packages.html#subpath-imports">subpath imports</a> can provide the same containment organization benefits as 756folders as modules, and work for both <code>require</code> and <code>import</code>.</p> 757</section><section><h3>Loading from <code>node_modules</code> folders<span><a class="mark" href="#loading-from-node_modules-folders" id="loading-from-node_modules-folders">#</a></span><a aria-hidden="true" class="legacy" id="modules_loading_from_node_modules_folders"></a></h3> 758 759<p>If the module identifier passed to <code>require()</code> is not a 760<a href="#core-modules">core</a> module, and does not begin with <code>'/'</code>, <code>'../'</code>, or 761<code>'./'</code>, then Node.js starts at the directory of the current module, and 762adds <code>/node_modules</code>, and attempts to load the module from that location. 763Node.js will not append <code>node_modules</code> to a path already ending in 764<code>node_modules</code>.</p> 765<p>If it is not found there, then it moves to the parent directory, and so 766on, until the root of the file system is reached.</p> 767<p>For example, if the file at <code>'/home/ry/projects/foo.js'</code> called 768<code>require('bar.js')</code>, then Node.js would look in the following locations, in 769this order:</p> 770<ul> 771<li><code>/home/ry/projects/node_modules/bar.js</code></li> 772<li><code>/home/ry/node_modules/bar.js</code></li> 773<li><code>/home/node_modules/bar.js</code></li> 774<li><code>/node_modules/bar.js</code></li> 775</ul> 776<p>This allows programs to localize their dependencies, so that they do not 777clash.</p> 778<p>It is possible to require specific files or sub modules distributed with a 779module by including a path suffix after the module name. For instance 780<code>require('example-module/path/to/file')</code> would resolve <code>path/to/file</code> 781relative to where <code>example-module</code> is located. The suffixed path follows the 782same module resolution semantics.</p> 783</section><section><h3>Loading from the global folders<span><a class="mark" href="#loading-from-the-global-folders" id="loading-from-the-global-folders">#</a></span><a aria-hidden="true" class="legacy" id="modules_loading_from_the_global_folders"></a></h3> 784 785<p>If the <code>NODE_PATH</code> environment variable is set to a colon-delimited list 786of absolute paths, then Node.js will search those paths for modules if they 787are not found elsewhere.</p> 788<p>On Windows, <code>NODE_PATH</code> is delimited by semicolons (<code>;</code>) instead of colons.</p> 789<p><code>NODE_PATH</code> was originally created to support loading modules from 790varying paths before the current <a href="#all-together">module resolution</a> algorithm was defined.</p> 791<p><code>NODE_PATH</code> is still supported, but is less necessary now that the Node.js 792ecosystem has settled on a convention for locating dependent modules. 793Sometimes deployments that rely on <code>NODE_PATH</code> show surprising behavior 794when people are unaware that <code>NODE_PATH</code> must be set. Sometimes a 795module's dependencies change, causing a different version (or even a 796different module) to be loaded as the <code>NODE_PATH</code> is searched.</p> 797<p>Additionally, Node.js will search in the following list of GLOBAL_FOLDERS:</p> 798<ul> 799<li>1: <code>$HOME/.node_modules</code></li> 800<li>2: <code>$HOME/.node_libraries</code></li> 801<li>3: <code>$PREFIX/lib/node</code></li> 802</ul> 803<p>Where <code>$HOME</code> is the user's home directory, and <code>$PREFIX</code> is the Node.js 804configured <code>node_prefix</code>.</p> 805<p>These are mostly for historic reasons.</p> 806<p>It is strongly encouraged to place dependencies in the local <code>node_modules</code> 807folder. These will be loaded faster, and more reliably.</p> 808</section><section><h3>The module wrapper<span><a class="mark" href="#the-module-wrapper" id="the-module-wrapper">#</a></span><a aria-hidden="true" class="legacy" id="modules_the_module_wrapper"></a></h3> 809 810<p>Before a module's code is executed, Node.js will wrap it with a function 811wrapper that looks like the following:</p> 812<pre><code class="language-js">(<span class="hljs-keyword">function</span>(<span class="hljs-params"><span class="hljs-built_in">exports</span>, <span class="hljs-built_in">require</span>, <span class="hljs-variable language_">module</span>, __filename, __dirname</span>) { 813<span class="hljs-comment">// Module code actually lives in here</span> 814});</code> <button class="copy-button">copy</button></pre> 815<p>By doing this, Node.js achieves a few things:</p> 816<ul> 817<li>It keeps top-level variables (defined with <code>var</code>, <code>const</code>, or <code>let</code>) scoped to 818the module rather than the global object.</li> 819<li>It helps to provide some global-looking variables that are actually specific 820to the module, such as: 821<ul> 822<li>The <code>module</code> and <code>exports</code> objects that the implementor can use to export 823values from the module.</li> 824<li>The convenience variables <code>__filename</code> and <code>__dirname</code>, containing the 825module's absolute filename and directory path.</li> 826</ul> 827</li> 828</ul> 829</section><section><h3>The module scope<span><a class="mark" href="#the-module-scope" id="the-module-scope">#</a></span><a aria-hidden="true" class="legacy" id="modules_the_module_scope"></a></h3> 830<h4><code>__dirname</code><span><a class="mark" href="#__dirname" id="__dirname">#</a></span><a aria-hidden="true" class="legacy" id="modules_dirname"></a></h4> 831<div class="api_metadata"> 832<span>Added in: v0.1.27</span> 833</div> 834 835<ul> 836<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 837</ul> 838<p>The directory name of the current module. This is the same as the 839<a href="path.html#pathdirnamepath"><code>path.dirname()</code></a> of the <a href="#__filename"><code>__filename</code></a>.</p> 840<p>Example: running <code>node example.js</code> from <code>/Users/mjr</code></p> 841<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(__dirname); 842<span class="hljs-comment">// Prints: /Users/mjr</span> 843<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(path.<span class="hljs-title function_">dirname</span>(__filename)); 844<span class="hljs-comment">// Prints: /Users/mjr</span></code> <button class="copy-button">copy</button></pre> 845<h4><code>__filename</code><span><a class="mark" href="#__filename" id="__filename">#</a></span><a aria-hidden="true" class="legacy" id="modules_filename"></a></h4> 846<div class="api_metadata"> 847<span>Added in: v0.0.1</span> 848</div> 849 850<ul> 851<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 852</ul> 853<p>The file name of the current module. This is the current module file's absolute 854path with symlinks resolved.</p> 855<p>For a main program this is not necessarily the same as the file name used in the 856command line.</p> 857<p>See <a href="#__dirname"><code>__dirname</code></a> for the directory name of the current module.</p> 858<p>Examples:</p> 859<p>Running <code>node example.js</code> from <code>/Users/mjr</code></p> 860<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(__filename); 861<span class="hljs-comment">// Prints: /Users/mjr/example.js</span> 862<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(__dirname); 863<span class="hljs-comment">// Prints: /Users/mjr</span></code> <button class="copy-button">copy</button></pre> 864<p>Given two modules: <code>a</code> and <code>b</code>, where <code>b</code> is a dependency of 865<code>a</code> and there is a directory structure of:</p> 866<ul> 867<li><code>/Users/mjr/app/a.js</code></li> 868<li><code>/Users/mjr/app/node_modules/b/b.js</code></li> 869</ul> 870<p>References to <code>__filename</code> within <code>b.js</code> will return 871<code>/Users/mjr/app/node_modules/b/b.js</code> while references to <code>__filename</code> within 872<code>a.js</code> will return <code>/Users/mjr/app/a.js</code>.</p> 873<h4><code>exports</code><span><a class="mark" href="#exports" id="exports">#</a></span><a aria-hidden="true" class="legacy" id="modules_exports"></a></h4> 874<div class="api_metadata"> 875<span>Added in: v0.1.12</span> 876</div> 877 878<ul> 879<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 880</ul> 881<p>A reference to the <code>module.exports</code> that is shorter to type. 882See the section about the <a href="#exports-shortcut">exports shortcut</a> for details on when to use 883<code>exports</code> and when to use <code>module.exports</code>.</p> 884<h4><code>module</code><span><a class="mark" href="#module" id="module">#</a></span><a aria-hidden="true" class="legacy" id="modules_module"></a></h4> 885<div class="api_metadata"> 886<span>Added in: v0.1.16</span> 887</div> 888 889<ul> 890<li><a href="modules.html#the-module-object" class="type"><module></a></li> 891</ul> 892<p>A reference to the current module, see the section about the 893<a href="#the-module-object"><code>module</code> object</a>. In particular, <code>module.exports</code> is used for defining what 894a module exports and makes available through <code>require()</code>.</p> 895<h4><code>require(id)</code><span><a class="mark" href="#requireid" id="requireid">#</a></span><a aria-hidden="true" class="legacy" id="modules_require_id"></a></h4> 896<div class="api_metadata"> 897<span>Added in: v0.1.13</span> 898</div> 899 900<ul> 901<li><code>id</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> module name or path</li> 902<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> exported module content</li> 903</ul> 904<p>Used to import modules, <code>JSON</code>, and local files. Modules can be imported 905from <code>node_modules</code>. Local modules and JSON files can be imported using 906a relative path (e.g. <code>./</code>, <code>./foo</code>, <code>./bar/baz</code>, <code>../foo</code>) that will be 907resolved against the directory named by <a href="#__dirname"><code>__dirname</code></a> (if defined) or 908the current working directory. The relative paths of POSIX style are resolved 909in an OS independent fashion, meaning that the examples above will work on 910Windows in the same way they would on Unix systems.</p> 911<pre><code class="language-js"><span class="hljs-comment">// Importing a local module with a path relative to the `__dirname` or current</span> 912<span class="hljs-comment">// working directory. (On Windows, this would resolve to .\path\myLocalModule.)</span> 913<span class="hljs-keyword">const</span> myLocalModule = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./path/myLocalModule'</span>); 914 915<span class="hljs-comment">// Importing a JSON file:</span> 916<span class="hljs-keyword">const</span> jsonData = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./path/filename.json'</span>); 917 918<span class="hljs-comment">// Importing a module from node_modules or Node.js built-in module:</span> 919<span class="hljs-keyword">const</span> crypto = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:crypto'</span>);</code> <button class="copy-button">copy</button></pre> 920<h5><code>require.cache</code><span><a class="mark" href="#requirecache" id="requirecache">#</a></span><a aria-hidden="true" class="legacy" id="modules_require_cache"></a></h5> 921<div class="api_metadata"> 922<span>Added in: v0.3.0</span> 923</div> 924<ul> 925<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 926</ul> 927<p>Modules are cached in this object when they are required. By deleting a key 928value from this object, the next <code>require</code> will reload the module. 929This does not apply to <a href="addons.html">native addons</a>, for which reloading will result in an 930error.</p> 931<p>Adding or replacing entries is also possible. This cache is checked before 932built-in modules and if a name matching a built-in module is added to the cache, 933only <code>node:</code>-prefixed require calls are going to receive the built-in module. 934Use with care!</p> 935<!-- eslint-disable node-core/no-duplicate-requires --> 936<pre><code class="language-js"><span class="hljs-keyword">const</span> assert = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:assert'</span>); 937<span class="hljs-keyword">const</span> realFs = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:fs'</span>); 938 939<span class="hljs-keyword">const</span> fakeFs = {}; 940<span class="hljs-built_in">require</span>.<span class="hljs-property">cache</span>.<span class="hljs-property">fs</span> = { <span class="hljs-attr">exports</span>: fakeFs }; 941 942assert.<span class="hljs-title function_">strictEqual</span>(<span class="hljs-built_in">require</span>(<span class="hljs-string">'fs'</span>), fakeFs); 943assert.<span class="hljs-title function_">strictEqual</span>(<span class="hljs-built_in">require</span>(<span class="hljs-string">'node:fs'</span>), realFs);</code> <button class="copy-button">copy</button></pre> 944<h5><code>require.extensions</code><span><a class="mark" href="#requireextensions" id="requireextensions">#</a></span><a aria-hidden="true" class="legacy" id="modules_require_extensions"></a></h5> 945<div class="api_metadata"> 946<span>Added in: v0.3.0</span><span>Deprecated since: v0.10.6</span> 947</div> 948<p></p><div class="api_stability api_stability_0"><a href="documentation.html#stability-index">Stability: 0</a> - Deprecated</div><p></p> 949<ul> 950<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 951</ul> 952<p>Instruct <code>require</code> on how to handle certain file extensions.</p> 953<p>Process files with the extension <code>.sjs</code> as <code>.js</code>:</p> 954<pre><code class="language-js"><span class="hljs-built_in">require</span>.<span class="hljs-property">extensions</span>[<span class="hljs-string">'.sjs'</span>] = <span class="hljs-built_in">require</span>.<span class="hljs-property">extensions</span>[<span class="hljs-string">'.js'</span>];</code> <button class="copy-button">copy</button></pre> 955<p><strong>Deprecated.</strong> In the past, this list has been used to load non-JavaScript 956modules into Node.js by compiling them on-demand. However, in practice, there 957are much better ways to do this, such as loading modules via some other Node.js 958program, or compiling them to JavaScript ahead of time.</p> 959<p>Avoid using <code>require.extensions</code>. Use could cause subtle bugs and resolving the 960extensions gets slower with each registered extension.</p> 961<h5><code>require.main</code><span><a class="mark" href="#requiremain" id="requiremain">#</a></span><a aria-hidden="true" class="legacy" id="modules_require_main"></a></h5> 962<div class="api_metadata"> 963<span>Added in: v0.1.17</span> 964</div> 965<ul> 966<li><a href="modules.html#the-module-object" class="type"><module></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Undefined_type" class="type"><undefined></a></li> 967</ul> 968<p>The <code>Module</code> object representing the entry script loaded when the Node.js 969process launched, or <code>undefined</code> if the entry point of the program is not a 970CommonJS module. 971See <a href="#accessing-the-main-module">"Accessing the main module"</a>.</p> 972<p>In <code>entry.js</code> script:</p> 973<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-built_in">require</span>.<span class="hljs-property">main</span>);</code> <button class="copy-button">copy</button></pre> 974<pre><code class="language-bash">node entry.js</code> <button class="copy-button">copy</button></pre> 975<!-- eslint-skip --> 976<pre><code class="language-js"><span class="hljs-title class_">Module</span> { 977 <span class="hljs-attr">id</span>: <span class="hljs-string">'.'</span>, 978 <span class="hljs-attr">path</span>: <span class="hljs-string">'/absolute/path/to'</span>, 979 <span class="hljs-attr">exports</span>: {}, 980 <span class="hljs-attr">filename</span>: <span class="hljs-string">'/absolute/path/to/entry.js'</span>, 981 <span class="hljs-attr">loaded</span>: <span class="hljs-literal">false</span>, 982 <span class="hljs-attr">children</span>: [], 983 <span class="hljs-attr">paths</span>: 984 [ <span class="hljs-string">'/absolute/path/to/node_modules'</span>, 985 <span class="hljs-string">'/absolute/path/node_modules'</span>, 986 <span class="hljs-string">'/absolute/node_modules'</span>, 987 <span class="hljs-string">'/node_modules'</span> ] }</code> <button class="copy-button">copy</button></pre> 988<h5><code>require.resolve(request[, options])</code><span><a class="mark" href="#requireresolverequest-options" id="requireresolverequest-options">#</a></span><a aria-hidden="true" class="legacy" id="modules_require_resolve_request_options"></a></h5> 989<div class="api_metadata"> 990<details class="changelog"><summary>History</summary> 991<table> 992<tbody><tr><th>Version</th><th>Changes</th></tr> 993<tr><td>v8.9.0</td> 994<td><p>The <code>paths</code> option is now supported.</p></td></tr> 995<tr><td>v0.3.0</td> 996<td><p><span>Added in: v0.3.0</span></p></td></tr> 997</tbody></table> 998</details> 999</div> 1000<ul> 1001<li><code>request</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The module path to resolve.</li> 1002<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> 1003<ul> 1004<li><code>paths</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a> Paths to resolve module location from. If present, these 1005paths are used instead of the default resolution paths, with the exception 1006of <a href="#loading-from-the-global-folders">GLOBAL_FOLDERS</a> like <code>$HOME/.node_modules</code>, which are 1007always included. Each of these paths is used as a starting point for 1008the module resolution algorithm, meaning that the <code>node_modules</code> hierarchy 1009is checked from this location.</li> 1010</ul> 1011</li> 1012<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1013</ul> 1014<p>Use the internal <code>require()</code> machinery to look up the location of a module, 1015but rather than loading the module, just return the resolved filename.</p> 1016<p>If the module can not be found, a <code>MODULE_NOT_FOUND</code> error is thrown.</p> 1017<h6><code>require.resolve.paths(request)</code><span><a class="mark" href="#requireresolvepathsrequest" id="requireresolvepathsrequest">#</a></span><a aria-hidden="true" class="legacy" id="modules_require_resolve_paths_request"></a></h6> 1018<div class="api_metadata"> 1019<span>Added in: v8.9.0</span> 1020</div> 1021<ul> 1022<li><code>request</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The module path whose lookup paths are being retrieved.</li> 1023<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Null_type" class="type"><null></a></li> 1024</ul> 1025<p>Returns an array containing the paths searched during resolution of <code>request</code> or 1026<code>null</code> if the <code>request</code> string references a core module, for example <code>http</code> or 1027<code>fs</code>.</p> 1028</section><section><h3>The <code>module</code> object<span><a class="mark" href="#the-module-object" id="the-module-object">#</a></span><a aria-hidden="true" class="legacy" id="modules_the_module_object"></a></h3> 1029<div class="api_metadata"> 1030<span>Added in: v0.1.16</span> 1031</div> 1032 1033 1034<ul> 1035<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 1036</ul> 1037<p>In each module, the <code>module</code> free variable is a reference to the object 1038representing the current module. For convenience, <code>module.exports</code> is 1039also accessible via the <code>exports</code> module-global. <code>module</code> is not actually 1040a global but rather local to each module.</p> 1041<h4><code>module.children</code><span><a class="mark" href="#modulechildren" id="modulechildren">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_children"></a></h4> 1042<div class="api_metadata"> 1043<span>Added in: v0.1.16</span> 1044</div> 1045<ul> 1046<li><a href="modules.html#the-module-object" class="type"><module[]></a></li> 1047</ul> 1048<p>The module objects required for the first time by this one.</p> 1049<h4><code>module.exports</code><span><a class="mark" href="#moduleexports" id="moduleexports">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_exports"></a></h4> 1050<div class="api_metadata"> 1051<span>Added in: v0.1.16</span> 1052</div> 1053<ul> 1054<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a></li> 1055</ul> 1056<p>The <code>module.exports</code> object is created by the <code>Module</code> system. Sometimes this is 1057not acceptable; many want their module to be an instance of some class. To do 1058this, assign the desired export object to <code>module.exports</code>. Assigning 1059the desired object to <code>exports</code> will simply rebind the local <code>exports</code> variable, 1060which is probably not what is desired.</p> 1061<p>For example, suppose we were making a module called <code>a.js</code>:</p> 1062<pre><code class="language-js"><span class="hljs-keyword">const</span> <span class="hljs-title class_">EventEmitter</span> = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:events'</span>); 1063 1064<span class="hljs-variable language_">module</span>.<span class="hljs-property">exports</span> = <span class="hljs-keyword">new</span> <span class="hljs-title class_">EventEmitter</span>(); 1065 1066<span class="hljs-comment">// Do some work, and after some time emit</span> 1067<span class="hljs-comment">// the 'ready' event from the module itself.</span> 1068<span class="hljs-built_in">setTimeout</span>(<span class="hljs-function">() =></span> { 1069 <span class="hljs-variable language_">module</span>.<span class="hljs-property">exports</span>.<span class="hljs-title function_">emit</span>(<span class="hljs-string">'ready'</span>); 1070}, <span class="hljs-number">1000</span>);</code> <button class="copy-button">copy</button></pre> 1071<p>Then in another file we could do:</p> 1072<pre><code class="language-js"><span class="hljs-keyword">const</span> a = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./a'</span>); 1073a.<span class="hljs-title function_">on</span>(<span class="hljs-string">'ready'</span>, <span class="hljs-function">() =></span> { 1074 <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'module "a" is ready'</span>); 1075});</code> <button class="copy-button">copy</button></pre> 1076<p>Assignment to <code>module.exports</code> must be done immediately. It cannot be 1077done in any callbacks. This does not work:</p> 1078<p><code>x.js</code>:</p> 1079<pre><code class="language-js"><span class="hljs-built_in">setTimeout</span>(<span class="hljs-function">() =></span> { 1080 <span class="hljs-variable language_">module</span>.<span class="hljs-property">exports</span> = { <span class="hljs-attr">a</span>: <span class="hljs-string">'hello'</span> }; 1081}, <span class="hljs-number">0</span>);</code> <button class="copy-button">copy</button></pre> 1082<p><code>y.js</code>:</p> 1083<pre><code class="language-js"><span class="hljs-keyword">const</span> x = <span class="hljs-built_in">require</span>(<span class="hljs-string">'./x'</span>); 1084<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(x.<span class="hljs-property">a</span>);</code> <button class="copy-button">copy</button></pre> 1085<h5><code>exports</code> shortcut<span><a class="mark" href="#exports-shortcut" id="exports-shortcut">#</a></span><a aria-hidden="true" class="legacy" id="modules_exports_shortcut"></a></h5> 1086<div class="api_metadata"> 1087<span>Added in: v0.1.16</span> 1088</div> 1089<p>The <code>exports</code> variable is available within a module's file-level scope, and is 1090assigned the value of <code>module.exports</code> before the module is evaluated.</p> 1091<p>It allows a shortcut, so that <code>module.exports.f = ...</code> can be written more 1092succinctly as <code>exports.f = ...</code>. However, be aware that like any variable, if a 1093new value is assigned to <code>exports</code>, it is no longer bound to <code>module.exports</code>:</p> 1094<pre><code class="language-js"><span class="hljs-variable language_">module</span>.<span class="hljs-property">exports</span>.<span class="hljs-property">hello</span> = <span class="hljs-literal">true</span>; <span class="hljs-comment">// Exported from require of module</span> 1095<span class="hljs-built_in">exports</span> = { <span class="hljs-attr">hello</span>: <span class="hljs-literal">false</span> }; <span class="hljs-comment">// Not exported, only available in the module</span></code> <button class="copy-button">copy</button></pre> 1096<p>When the <code>module.exports</code> property is being completely replaced by a new 1097object, it is common to also reassign <code>exports</code>:</p> 1098<!-- eslint-disable func-name-matching --> 1099<pre><code class="language-js"><span class="hljs-variable language_">module</span>.<span class="hljs-property">exports</span> = <span class="hljs-built_in">exports</span> = <span class="hljs-keyword">function</span> <span class="hljs-title function_">Constructor</span>(<span class="hljs-params"></span>) { 1100 <span class="hljs-comment">// ... etc.</span> 1101};</code> <button class="copy-button">copy</button></pre> 1102<p>To illustrate the behavior, imagine this hypothetical implementation of 1103<code>require()</code>, which is quite similar to what is actually done by <code>require()</code>:</p> 1104<pre><code class="language-js"><span class="hljs-keyword">function</span> <span class="hljs-title function_">require</span>(<span class="hljs-params"><span class="hljs-comment">/* ... */</span></span>) { 1105 <span class="hljs-keyword">const</span> <span class="hljs-variable language_">module</span> = { <span class="hljs-attr">exports</span>: {} }; 1106 (<span class="hljs-function">(<span class="hljs-params"><span class="hljs-variable language_">module</span>, <span class="hljs-built_in">exports</span></span>) =></span> { 1107 <span class="hljs-comment">// Module code here. In this example, define a function.</span> 1108 <span class="hljs-keyword">function</span> <span class="hljs-title function_">someFunc</span>(<span class="hljs-params"></span>) {} 1109 <span class="hljs-built_in">exports</span> = someFunc; 1110 <span class="hljs-comment">// At this point, exports is no longer a shortcut to module.exports, and</span> 1111 <span class="hljs-comment">// this module will still export an empty default object.</span> 1112 <span class="hljs-variable language_">module</span>.<span class="hljs-property">exports</span> = someFunc; 1113 <span class="hljs-comment">// At this point, the module will now export someFunc, instead of the</span> 1114 <span class="hljs-comment">// default object.</span> 1115 })(<span class="hljs-variable language_">module</span>, <span class="hljs-variable language_">module</span>.<span class="hljs-property">exports</span>); 1116 <span class="hljs-keyword">return</span> <span class="hljs-variable language_">module</span>.<span class="hljs-property">exports</span>; 1117}</code> <button class="copy-button">copy</button></pre> 1118<h4><code>module.filename</code><span><a class="mark" href="#modulefilename" id="modulefilename">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_filename"></a></h4> 1119<div class="api_metadata"> 1120<span>Added in: v0.1.16</span> 1121</div> 1122<ul> 1123<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1124</ul> 1125<p>The fully resolved filename of the module.</p> 1126<h4><code>module.id</code><span><a class="mark" href="#moduleid" id="moduleid">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_id"></a></h4> 1127<div class="api_metadata"> 1128<span>Added in: v0.1.16</span> 1129</div> 1130<ul> 1131<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1132</ul> 1133<p>The identifier for the module. Typically this is the fully resolved 1134filename.</p> 1135<h4><code>module.isPreloading</code><span><a class="mark" href="#moduleispreloading" id="moduleispreloading">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_ispreloading"></a></h4> 1136<div class="api_metadata"> 1137<span>Added in: v15.4.0, v14.17.0</span> 1138</div> 1139<ul> 1140<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> <code>true</code> if the module is running during the Node.js preload 1141phase.</li> 1142</ul> 1143<h4><code>module.loaded</code><span><a class="mark" href="#moduleloaded" id="moduleloaded">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_loaded"></a></h4> 1144<div class="api_metadata"> 1145<span>Added in: v0.1.16</span> 1146</div> 1147<ul> 1148<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 1149</ul> 1150<p>Whether or not the module is done loading, or is in the process of 1151loading.</p> 1152<h4><code>module.parent</code><span><a class="mark" href="#moduleparent" id="moduleparent">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_parent"></a></h4> 1153<div class="api_metadata"> 1154<span>Added in: v0.1.16</span><span>Deprecated since: v14.6.0, v12.19.0</span> 1155</div> 1156<p></p><div class="api_stability api_stability_0"><a href="documentation.html#stability-index">Stability: 0</a> - Deprecated: Please use <a href="#requiremain"><code>require.main</code></a> and 1157<a href="#modulechildren"><code>module.children</code></a> instead.</div><p></p> 1158<ul> 1159<li><a href="modules.html#the-module-object" class="type"><module></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Null_type" class="type"><null></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Undefined_type" class="type"><undefined></a></li> 1160</ul> 1161<p>The module that first required this one, or <code>null</code> if the current module is the 1162entry point of the current process, or <code>undefined</code> if the module was loaded by 1163something that is not a CommonJS module (E.G.: REPL or <code>import</code>).</p> 1164<h4><code>module.path</code><span><a class="mark" href="#modulepath" id="modulepath">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_path"></a></h4> 1165<div class="api_metadata"> 1166<span>Added in: v11.14.0</span> 1167</div> 1168<ul> 1169<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1170</ul> 1171<p>The directory name of the module. This is usually the same as the 1172<a href="path.html#pathdirnamepath"><code>path.dirname()</code></a> of the <a href="#moduleid"><code>module.id</code></a>.</p> 1173<h4><code>module.paths</code><span><a class="mark" href="#modulepaths" id="modulepaths">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_paths"></a></h4> 1174<div class="api_metadata"> 1175<span>Added in: v0.4.0</span> 1176</div> 1177<ul> 1178<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a></li> 1179</ul> 1180<p>The search paths for the module.</p> 1181<h4><code>module.require(id)</code><span><a class="mark" href="#modulerequireid" id="modulerequireid">#</a></span><a aria-hidden="true" class="legacy" id="modules_module_require_id"></a></h4> 1182<div class="api_metadata"> 1183<span>Added in: v0.5.1</span> 1184</div> 1185<ul> 1186<li><code>id</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a></li> 1187<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> exported module content</li> 1188</ul> 1189<p>The <code>module.require()</code> method provides a way to load a module as if 1190<code>require()</code> was called from the original module.</p> 1191<p>In order to do this, it is necessary to get a reference to the <code>module</code> object. 1192Since <code>require()</code> returns the <code>module.exports</code>, and the <code>module</code> is typically 1193<em>only</em> available within a specific module's code, it must be explicitly exported 1194in order to be used.</p> 1195</section><section><h3>The <code>Module</code> object<span><a class="mark" href="#the-module-object_1" id="the-module-object_1">#</a></span><a aria-hidden="true" class="legacy" id="modules_the_module_object_1"></a></h3> 1196<p>This section was moved to 1197<a href="module.html#the-module-object">Modules: <code>module</code> core module</a>.</p> 1198<!-- Anchors to make sure old links find a target --> 1199<ul> 1200<li><a id="modules_module_builtinmodules" href="module.html#modulebuiltinmodules"><code>module.builtinModules</code></a></li> 1201<li><a id="modules_module_createrequire_filename" href="module.html#modulecreaterequirefilename"><code>module.createRequire(filename)</code></a></li> 1202<li><a id="modules_module_syncbuiltinesmexports" href="module.html#modulesyncbuiltinesmexports"><code>module.syncBuiltinESMExports()</code></a></li> 1203</ul> 1204</section><section><h3>Source map v3 support<span><a class="mark" href="#source-map-v3-support" id="source-map-v3-support">#</a></span><a aria-hidden="true" class="legacy" id="modules_source_map_v3_support"></a></h3> 1205<p>This section was moved to 1206<a href="module.html#source-map-v3-support">Modules: <code>module</code> core module</a>.</p> 1207<!-- Anchors to make sure old links find a target --> 1208<ul> 1209<li><a id="modules_module_findsourcemap_path_error" href="module.html#modulefindsourcemappath"><code>module.findSourceMap(path)</code></a></li> 1210<li><a id="modules_class_module_sourcemap" href="module.html#class-modulesourcemap">Class: <code>module.SourceMap</code></a> 1211<ul> 1212<li><a id="modules_new_sourcemap_payload" href="module.html#new-sourcemappayload"><code>new SourceMap(payload)</code></a></li> 1213<li><a id="modules_sourcemap_payload" href="module.html#sourcemappayload"><code>sourceMap.payload</code></a></li> 1214<li><a id="modules_sourcemap_findentry_linenumber_columnnumber" href="module.html#sourcemapfindentrylinenumber-columnnumber"><code>sourceMap.findEntry(lineNumber, columnNumber)</code></a></li> 1215</ul> 1216</li> 1217</ul></section> 1218 <!-- API END --> 1219 </div> 1220 </div> 1221 </div> 1222</body> 1223</html> 1224