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1001cb0ef41Sopenharmony_ci <button class="theme-toggle-btn" id="theme-toggle-btn" title="Toggle dark mode/light mode" aria-label="Toggle dark mode/light mode" hidden> 1011cb0ef41Sopenharmony_ci <svg xmlns="http://www.w3.org/2000/svg" class="icon dark-icon" height="24" width="24"> 1021cb0ef41Sopenharmony_ci <path fill="none" d="M0 0h24v24H0z" /> 1031cb0ef41Sopenharmony_ci <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"/> 1041cb0ef41Sopenharmony_ci <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"/> 1051cb0ef41Sopenharmony_ci </svg> 1061cb0ef41Sopenharmony_ci <svg xmlns="http://www.w3.org/2000/svg" class="icon light-icon" height="24" width="24"> 1071cb0ef41Sopenharmony_ci <path d="M0 0h24v24H0z" fill="none" /> 1081cb0ef41Sopenharmony_ci <path d="M6.76 4.84l-1.8-1.79-1.41 1.41 1.79 1.79 1.42-1.41zM4 10.5H1v2h3v-2zm9-9.95h-2V3.5h2V.55zm7.45 3.91l-1.41-1.41-1.79 1.79 1.41 1.41 1.79-1.79zm-3.21 13.7l1.79 1.8 1.41-1.41-1.8-1.79-1.4 1.4zM20 10.5v2h3v-2h-3zm-8-5c-3.31 0-6 2.69-6 6s2.69 6 6 6 6-2.69 6-6-2.69-6-6-6zm-1 16.95h2V19.5h-2v2.95zm-7.45-3.91l1.41 1.41 1.79-1.8-1.41-1.41-1.79 1.8z"/> 1091cb0ef41Sopenharmony_ci </svg> 1101cb0ef41Sopenharmony_ci </button> 1111cb0ef41Sopenharmony_ci </div> 1121cb0ef41Sopenharmony_ci <div id="gtoc"> 1131cb0ef41Sopenharmony_ci <ul> 1141cb0ef41Sopenharmony_ci <li class="pinned-header">Node.js v18.20.1</li> 1151cb0ef41Sopenharmony_ci 1161cb0ef41Sopenharmony_ci <li class="picker-header"> 1171cb0ef41Sopenharmony_ci <a href="#"> 1181cb0ef41Sopenharmony_ci <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 1191cb0ef41Sopenharmony_ci Table of contents 1201cb0ef41Sopenharmony_ci </a> 1211cb0ef41Sopenharmony_ci 1221cb0ef41Sopenharmony_ci <div class="picker"><div class="toc"><ul> 1231cb0ef41Sopenharmony_ci<li><span class="stability_2"><a href="#repl">REPL</a></span> 1241cb0ef41Sopenharmony_ci<ul> 1251cb0ef41Sopenharmony_ci<li><a href="#design-and-features">Design and features</a> 1261cb0ef41Sopenharmony_ci<ul> 1271cb0ef41Sopenharmony_ci<li><a href="#commands-and-special-keys">Commands and special keys</a></li> 1281cb0ef41Sopenharmony_ci<li><a href="#default-evaluation">Default evaluation</a> 1291cb0ef41Sopenharmony_ci<ul> 1301cb0ef41Sopenharmony_ci<li><a href="#javascript-expressions">JavaScript expressions</a></li> 1311cb0ef41Sopenharmony_ci<li><a href="#global-and-local-scope">Global and local scope</a></li> 1321cb0ef41Sopenharmony_ci<li><a href="#accessing-core-nodejs-modules">Accessing core Node.js modules</a></li> 1331cb0ef41Sopenharmony_ci<li><a href="#global-uncaught-exceptions">Global uncaught exceptions</a></li> 1341cb0ef41Sopenharmony_ci<li><a href="#assignment-of-the-_-underscore-variable">Assignment of the <code>_</code> (underscore) variable</a></li> 1351cb0ef41Sopenharmony_ci<li><a href="#await-keyword"><code>await</code> keyword</a></li> 1361cb0ef41Sopenharmony_ci</ul> 1371cb0ef41Sopenharmony_ci</li> 1381cb0ef41Sopenharmony_ci<li><a href="#reverse-i-search">Reverse-i-search</a></li> 1391cb0ef41Sopenharmony_ci<li><a href="#custom-evaluation-functions">Custom evaluation functions</a> 1401cb0ef41Sopenharmony_ci<ul> 1411cb0ef41Sopenharmony_ci<li><a href="#recoverable-errors">Recoverable errors</a></li> 1421cb0ef41Sopenharmony_ci</ul> 1431cb0ef41Sopenharmony_ci</li> 1441cb0ef41Sopenharmony_ci<li><a href="#customizing-repl-output">Customizing REPL output</a></li> 1451cb0ef41Sopenharmony_ci</ul> 1461cb0ef41Sopenharmony_ci</li> 1471cb0ef41Sopenharmony_ci<li><a href="#class-replserver">Class: <code>REPLServer</code></a> 1481cb0ef41Sopenharmony_ci<ul> 1491cb0ef41Sopenharmony_ci<li><a href="#event-exit">Event: <code>'exit'</code></a></li> 1501cb0ef41Sopenharmony_ci<li><a href="#event-reset">Event: <code>'reset'</code></a></li> 1511cb0ef41Sopenharmony_ci<li><a href="#replserverdefinecommandkeyword-cmd"><code>replServer.defineCommand(keyword, cmd)</code></a></li> 1521cb0ef41Sopenharmony_ci<li><a href="#replserverdisplaypromptpreservecursor"><code>replServer.displayPrompt([preserveCursor])</code></a></li> 1531cb0ef41Sopenharmony_ci<li><a href="#replserverclearbufferedcommand"><code>replServer.clearBufferedCommand()</code></a></li> 1541cb0ef41Sopenharmony_ci<li><span class="stability_0"><a href="#replserverparsereplkeywordkeyword-rest"><code>replServer.parseREPLKeyword(keyword[, rest])</code></a></span></li> 1551cb0ef41Sopenharmony_ci<li><a href="#replserversetuphistoryhistorypath-callback"><code>replServer.setupHistory(historyPath, callback)</code></a></li> 1561cb0ef41Sopenharmony_ci</ul> 1571cb0ef41Sopenharmony_ci</li> 1581cb0ef41Sopenharmony_ci<li><a href="#replbuiltinmodules"><code>repl.builtinModules</code></a></li> 1591cb0ef41Sopenharmony_ci<li><a href="#replstartoptions"><code>repl.start([options])</code></a></li> 1601cb0ef41Sopenharmony_ci<li><a href="#the-nodejs-repl">The Node.js REPL</a> 1611cb0ef41Sopenharmony_ci<ul> 1621cb0ef41Sopenharmony_ci<li><a href="#environment-variable-options">Environment variable options</a></li> 1631cb0ef41Sopenharmony_ci<li><a href="#persistent-history">Persistent history</a></li> 1641cb0ef41Sopenharmony_ci<li><a href="#using-the-nodejs-repl-with-advanced-line-editors">Using the Node.js REPL with advanced line-editors</a></li> 1651cb0ef41Sopenharmony_ci<li><a href="#starting-multiple-repl-instances-against-a-single-running-instance">Starting multiple REPL instances against a single running instance</a></li> 1661cb0ef41Sopenharmony_ci</ul> 1671cb0ef41Sopenharmony_ci</li> 1681cb0ef41Sopenharmony_ci</ul> 1691cb0ef41Sopenharmony_ci</li> 1701cb0ef41Sopenharmony_ci</ul></div></div> 1711cb0ef41Sopenharmony_ci </li> 1721cb0ef41Sopenharmony_ci 1731cb0ef41Sopenharmony_ci 1741cb0ef41Sopenharmony_ci <li class="picker-header"> 1751cb0ef41Sopenharmony_ci <a href="#"> 1761cb0ef41Sopenharmony_ci <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 1771cb0ef41Sopenharmony_ci Index 1781cb0ef41Sopenharmony_ci </a> 1791cb0ef41Sopenharmony_ci 1801cb0ef41Sopenharmony_ci <div class="picker"><ul> 1811cb0ef41Sopenharmony_ci<li><a href="documentation.html" class="nav-documentation">About this documentation</a></li> 1821cb0ef41Sopenharmony_ci<li><a href="synopsis.html" class="nav-synopsis">Usage and example</a></li> 1831cb0ef41Sopenharmony_ci 1841cb0ef41Sopenharmony_ci <li> 1851cb0ef41Sopenharmony_ci <a href="index.html">Index</a> 1861cb0ef41Sopenharmony_ci </li> 1871cb0ef41Sopenharmony_ci </ul> 1881cb0ef41Sopenharmony_ci 1891cb0ef41Sopenharmony_ci<hr class="line"> 1901cb0ef41Sopenharmony_ci<ul> 1911cb0ef41Sopenharmony_ci<li><a href="assert.html" class="nav-assert">Assertion testing</a></li> 1921cb0ef41Sopenharmony_ci<li><a href="async_context.html" 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2241cb0ef41Sopenharmony_ci<li><a href="path.html" class="nav-path">Path</a></li> 2251cb0ef41Sopenharmony_ci<li><a href="perf_hooks.html" class="nav-perf_hooks">Performance hooks</a></li> 2261cb0ef41Sopenharmony_ci<li><a href="permissions.html" class="nav-permissions">Permissions</a></li> 2271cb0ef41Sopenharmony_ci<li><a href="process.html" class="nav-process">Process</a></li> 2281cb0ef41Sopenharmony_ci<li><a href="punycode.html" class="nav-punycode">Punycode</a></li> 2291cb0ef41Sopenharmony_ci<li><a href="querystring.html" class="nav-querystring">Query strings</a></li> 2301cb0ef41Sopenharmony_ci<li><a href="readline.html" class="nav-readline">Readline</a></li> 2311cb0ef41Sopenharmony_ci<li><a href="repl.html" class="nav-repl active">REPL</a></li> 2321cb0ef41Sopenharmony_ci<li><a href="report.html" class="nav-report">Report</a></li> 2331cb0ef41Sopenharmony_ci<li><a href="single-executable-applications.html" class="nav-single-executable-applications">Single executable applications</a></li> 2341cb0ef41Sopenharmony_ci<li><a href="stream.html" class="nav-stream">Stream</a></li> 2351cb0ef41Sopenharmony_ci<li><a href="string_decoder.html" class="nav-string_decoder">String decoder</a></li> 2361cb0ef41Sopenharmony_ci<li><a href="test.html" class="nav-test">Test runner</a></li> 2371cb0ef41Sopenharmony_ci<li><a href="timers.html" class="nav-timers">Timers</a></li> 2381cb0ef41Sopenharmony_ci<li><a href="tls.html" class="nav-tls">TLS/SSL</a></li> 2391cb0ef41Sopenharmony_ci<li><a href="tracing.html" class="nav-tracing">Trace events</a></li> 2401cb0ef41Sopenharmony_ci<li><a href="tty.html" class="nav-tty">TTY</a></li> 2411cb0ef41Sopenharmony_ci<li><a href="dgram.html" class="nav-dgram">UDP/datagram</a></li> 2421cb0ef41Sopenharmony_ci<li><a href="url.html" class="nav-url">URL</a></li> 2431cb0ef41Sopenharmony_ci<li><a href="util.html" class="nav-util">Utilities</a></li> 2441cb0ef41Sopenharmony_ci<li><a href="v8.html" class="nav-v8">V8</a></li> 2451cb0ef41Sopenharmony_ci<li><a href="vm.html" class="nav-vm">VM</a></li> 2461cb0ef41Sopenharmony_ci<li><a href="wasi.html" class="nav-wasi">WASI</a></li> 2471cb0ef41Sopenharmony_ci<li><a href="webcrypto.html" class="nav-webcrypto">Web Crypto API</a></li> 2481cb0ef41Sopenharmony_ci<li><a href="webstreams.html" class="nav-webstreams">Web Streams API</a></li> 2491cb0ef41Sopenharmony_ci<li><a href="worker_threads.html" class="nav-worker_threads">Worker threads</a></li> 2501cb0ef41Sopenharmony_ci<li><a href="zlib.html" class="nav-zlib">Zlib</a></li> 2511cb0ef41Sopenharmony_ci</ul> 2521cb0ef41Sopenharmony_ci<hr class="line"> 2531cb0ef41Sopenharmony_ci<ul> 2541cb0ef41Sopenharmony_ci<li><a href="https://github.com/nodejs/node" class="nav-https-github-com-nodejs-node">Code repository and issue tracker</a></li> 2551cb0ef41Sopenharmony_ci</ul></div> 2561cb0ef41Sopenharmony_ci </li> 2571cb0ef41Sopenharmony_ci 2581cb0ef41Sopenharmony_ci 2591cb0ef41Sopenharmony_ci <li class="picker-header"> 2601cb0ef41Sopenharmony_ci <a href="#"> 2611cb0ef41Sopenharmony_ci <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 2621cb0ef41Sopenharmony_ci Other versions 2631cb0ef41Sopenharmony_ci </a> 2641cb0ef41Sopenharmony_ci <div class="picker"><ol id="alt-docs"><li><a href="https://nodejs.org/docs/latest-v21.x/api/repl.html">21.x</a></li> 2651cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v20.x/api/repl.html">20.x <b>LTS</b></a></li> 2661cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v19.x/api/repl.html">19.x</a></li> 2671cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v18.x/api/repl.html">18.x <b>LTS</b></a></li> 2681cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v17.x/api/repl.html">17.x</a></li> 2691cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v16.x/api/repl.html">16.x</a></li> 2701cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v15.x/api/repl.html">15.x</a></li> 2711cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v14.x/api/repl.html">14.x</a></li> 2721cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v13.x/api/repl.html">13.x</a></li> 2731cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v12.x/api/repl.html">12.x</a></li> 2741cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v11.x/api/repl.html">11.x</a></li> 2751cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v10.x/api/repl.html">10.x</a></li> 2761cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v9.x/api/repl.html">9.x</a></li> 2771cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v8.x/api/repl.html">8.x</a></li> 2781cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v7.x/api/repl.html">7.x</a></li> 2791cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v6.x/api/repl.html">6.x</a></li> 2801cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v5.x/api/repl.html">5.x</a></li> 2811cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v4.x/api/repl.html">4.x</a></li> 2821cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v0.12.x/api/repl.html">0.12.x</a></li> 2831cb0ef41Sopenharmony_ci<li><a href="https://nodejs.org/docs/latest-v0.10.x/api/repl.html">0.10.x</a></li></ol></div> 2841cb0ef41Sopenharmony_ci </li> 2851cb0ef41Sopenharmony_ci 2861cb0ef41Sopenharmony_ci <li class="picker-header"> 2871cb0ef41Sopenharmony_ci <a href="#"> 2881cb0ef41Sopenharmony_ci <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> 2891cb0ef41Sopenharmony_ci Options 2901cb0ef41Sopenharmony_ci </a> 2911cb0ef41Sopenharmony_ci 2921cb0ef41Sopenharmony_ci <div class="picker"> 2931cb0ef41Sopenharmony_ci <ul> 2941cb0ef41Sopenharmony_ci <li> 2951cb0ef41Sopenharmony_ci <a href="all.html">View on single page</a> 2961cb0ef41Sopenharmony_ci </li> 2971cb0ef41Sopenharmony_ci <li> 2981cb0ef41Sopenharmony_ci <a href="repl.json">View as JSON</a> 2991cb0ef41Sopenharmony_ci </li> 3001cb0ef41Sopenharmony_ci <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/main/doc/api/repl.md">Edit on GitHub</a></li> 3011cb0ef41Sopenharmony_ci </ul> 3021cb0ef41Sopenharmony_ci </div> 3031cb0ef41Sopenharmony_ci </li> 3041cb0ef41Sopenharmony_ci </ul> 3051cb0ef41Sopenharmony_ci </div> 3061cb0ef41Sopenharmony_ci <hr> 3071cb0ef41Sopenharmony_ci </header> 3081cb0ef41Sopenharmony_ci 3091cb0ef41Sopenharmony_ci <details id="toc" open><summary>Table of contents</summary><ul> 3101cb0ef41Sopenharmony_ci<li><span class="stability_2"><a href="#repl">REPL</a></span> 3111cb0ef41Sopenharmony_ci<ul> 3121cb0ef41Sopenharmony_ci<li><a href="#design-and-features">Design and features</a> 3131cb0ef41Sopenharmony_ci<ul> 3141cb0ef41Sopenharmony_ci<li><a href="#commands-and-special-keys">Commands and special keys</a></li> 3151cb0ef41Sopenharmony_ci<li><a href="#default-evaluation">Default evaluation</a> 3161cb0ef41Sopenharmony_ci<ul> 3171cb0ef41Sopenharmony_ci<li><a href="#javascript-expressions">JavaScript expressions</a></li> 3181cb0ef41Sopenharmony_ci<li><a href="#global-and-local-scope">Global and local scope</a></li> 3191cb0ef41Sopenharmony_ci<li><a href="#accessing-core-nodejs-modules">Accessing core Node.js modules</a></li> 3201cb0ef41Sopenharmony_ci<li><a href="#global-uncaught-exceptions">Global uncaught exceptions</a></li> 3211cb0ef41Sopenharmony_ci<li><a href="#assignment-of-the-_-underscore-variable">Assignment of the <code>_</code> (underscore) variable</a></li> 3221cb0ef41Sopenharmony_ci<li><a href="#await-keyword"><code>await</code> keyword</a></li> 3231cb0ef41Sopenharmony_ci</ul> 3241cb0ef41Sopenharmony_ci</li> 3251cb0ef41Sopenharmony_ci<li><a href="#reverse-i-search">Reverse-i-search</a></li> 3261cb0ef41Sopenharmony_ci<li><a href="#custom-evaluation-functions">Custom evaluation functions</a> 3271cb0ef41Sopenharmony_ci<ul> 3281cb0ef41Sopenharmony_ci<li><a href="#recoverable-errors">Recoverable errors</a></li> 3291cb0ef41Sopenharmony_ci</ul> 3301cb0ef41Sopenharmony_ci</li> 3311cb0ef41Sopenharmony_ci<li><a href="#customizing-repl-output">Customizing REPL output</a></li> 3321cb0ef41Sopenharmony_ci</ul> 3331cb0ef41Sopenharmony_ci</li> 3341cb0ef41Sopenharmony_ci<li><a href="#class-replserver">Class: <code>REPLServer</code></a> 3351cb0ef41Sopenharmony_ci<ul> 3361cb0ef41Sopenharmony_ci<li><a href="#event-exit">Event: <code>'exit'</code></a></li> 3371cb0ef41Sopenharmony_ci<li><a href="#event-reset">Event: <code>'reset'</code></a></li> 3381cb0ef41Sopenharmony_ci<li><a href="#replserverdefinecommandkeyword-cmd"><code>replServer.defineCommand(keyword, cmd)</code></a></li> 3391cb0ef41Sopenharmony_ci<li><a href="#replserverdisplaypromptpreservecursor"><code>replServer.displayPrompt([preserveCursor])</code></a></li> 3401cb0ef41Sopenharmony_ci<li><a href="#replserverclearbufferedcommand"><code>replServer.clearBufferedCommand()</code></a></li> 3411cb0ef41Sopenharmony_ci<li><span class="stability_0"><a href="#replserverparsereplkeywordkeyword-rest"><code>replServer.parseREPLKeyword(keyword[, rest])</code></a></span></li> 3421cb0ef41Sopenharmony_ci<li><a href="#replserversetuphistoryhistorypath-callback"><code>replServer.setupHistory(historyPath, callback)</code></a></li> 3431cb0ef41Sopenharmony_ci</ul> 3441cb0ef41Sopenharmony_ci</li> 3451cb0ef41Sopenharmony_ci<li><a href="#replbuiltinmodules"><code>repl.builtinModules</code></a></li> 3461cb0ef41Sopenharmony_ci<li><a href="#replstartoptions"><code>repl.start([options])</code></a></li> 3471cb0ef41Sopenharmony_ci<li><a href="#the-nodejs-repl">The Node.js REPL</a> 3481cb0ef41Sopenharmony_ci<ul> 3491cb0ef41Sopenharmony_ci<li><a href="#environment-variable-options">Environment variable options</a></li> 3501cb0ef41Sopenharmony_ci<li><a href="#persistent-history">Persistent history</a></li> 3511cb0ef41Sopenharmony_ci<li><a href="#using-the-nodejs-repl-with-advanced-line-editors">Using the Node.js REPL with advanced line-editors</a></li> 3521cb0ef41Sopenharmony_ci<li><a href="#starting-multiple-repl-instances-against-a-single-running-instance">Starting multiple REPL instances against a single running instance</a></li> 3531cb0ef41Sopenharmony_ci</ul> 3541cb0ef41Sopenharmony_ci</li> 3551cb0ef41Sopenharmony_ci</ul> 3561cb0ef41Sopenharmony_ci</li> 3571cb0ef41Sopenharmony_ci</ul></details> 3581cb0ef41Sopenharmony_ci 3591cb0ef41Sopenharmony_ci <div id="apicontent"> 3601cb0ef41Sopenharmony_ci <h2>REPL<span><a class="mark" href="#repl" id="repl">#</a></span><a aria-hidden="true" class="legacy" id="repl_repl"></a></h2> 3611cb0ef41Sopenharmony_ci 3621cb0ef41Sopenharmony_ci<p></p><div class="api_stability api_stability_2"><a href="documentation.html#stability-index">Stability: 2</a> - Stable</div><p></p> 3631cb0ef41Sopenharmony_ci<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v18.20.1/lib/repl.js">lib/repl.js</a></p> 3641cb0ef41Sopenharmony_ci<p>The <code>node:repl</code> module provides a Read-Eval-Print-Loop (REPL) implementation 3651cb0ef41Sopenharmony_cithat is available both as a standalone program or includible in other 3661cb0ef41Sopenharmony_ciapplications. It can be accessed using:</p> 3671cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> repl = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:repl'</span>);</code> <button class="copy-button">copy</button></pre> 3681cb0ef41Sopenharmony_ci<section><h3>Design and features<span><a class="mark" href="#design-and-features" id="design-and-features">#</a></span><a aria-hidden="true" class="legacy" id="repl_design_and_features"></a></h3> 3691cb0ef41Sopenharmony_ci<p>The <code>node:repl</code> module exports the <a href="#class-replserver"><code>repl.REPLServer</code></a> class. While running, 3701cb0ef41Sopenharmony_ciinstances of <a href="#class-replserver"><code>repl.REPLServer</code></a> will accept individual lines of user input, 3711cb0ef41Sopenharmony_cievaluate those according to a user-defined evaluation function, then output the 3721cb0ef41Sopenharmony_ciresult. Input and output may be from <code>stdin</code> and <code>stdout</code>, respectively, or may 3731cb0ef41Sopenharmony_cibe connected to any Node.js <a href="stream.html">stream</a>.</p> 3741cb0ef41Sopenharmony_ci<p>Instances of <a href="#class-replserver"><code>repl.REPLServer</code></a> support automatic completion of inputs, 3751cb0ef41Sopenharmony_cicompletion preview, simplistic Emacs-style line editing, multi-line inputs, 3761cb0ef41Sopenharmony_ci<a href="https://en.wikipedia.org/wiki/Z_shell">ZSH</a>-like reverse-i-search, <a href="https://en.wikipedia.org/wiki/Z_shell">ZSH</a>-like substring-based history search, 3771cb0ef41Sopenharmony_ciANSI-styled output, saving and restoring current REPL session state, error 3781cb0ef41Sopenharmony_cirecovery, and customizable evaluation functions. Terminals that do not support 3791cb0ef41Sopenharmony_ciANSI styles and Emacs-style line editing automatically fall back to a limited 3801cb0ef41Sopenharmony_cifeature set.</p> 3811cb0ef41Sopenharmony_ci<h4>Commands and special keys<span><a class="mark" href="#commands-and-special-keys" id="commands-and-special-keys">#</a></span><a aria-hidden="true" class="legacy" id="repl_commands_and_special_keys"></a></h4> 3821cb0ef41Sopenharmony_ci<p>The following special commands are supported by all REPL instances:</p> 3831cb0ef41Sopenharmony_ci<ul> 3841cb0ef41Sopenharmony_ci<li><code>.break</code>: When in the process of inputting a multi-line expression, enter 3851cb0ef41Sopenharmony_cithe <code>.break</code> command (or press <kbd>Ctrl</kbd>+<kbd>C</kbd>) to abort 3861cb0ef41Sopenharmony_cifurther input or processing of that expression.</li> 3871cb0ef41Sopenharmony_ci<li><code>.clear</code>: Resets the REPL <code>context</code> to an empty object and clears any 3881cb0ef41Sopenharmony_cimulti-line expression being input.</li> 3891cb0ef41Sopenharmony_ci<li><code>.exit</code>: Close the I/O stream, causing the REPL to exit.</li> 3901cb0ef41Sopenharmony_ci<li><code>.help</code>: Show this list of special commands.</li> 3911cb0ef41Sopenharmony_ci<li><code>.save</code>: Save the current REPL session to a file: 3921cb0ef41Sopenharmony_ci<code>> .save ./file/to/save.js</code></li> 3931cb0ef41Sopenharmony_ci<li><code>.load</code>: Load a file into the current REPL session. 3941cb0ef41Sopenharmony_ci<code>> .load ./file/to/load.js</code></li> 3951cb0ef41Sopenharmony_ci<li><code>.editor</code>: Enter editor mode (<kbd>Ctrl</kbd>+<kbd>D</kbd> to 3961cb0ef41Sopenharmony_cifinish, <kbd>Ctrl</kbd>+<kbd>C</kbd> to cancel).</li> 3971cb0ef41Sopenharmony_ci</ul> 3981cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash">.editor</span> 3991cb0ef41Sopenharmony_ci// Entering editor mode (^D to finish, ^C to cancel) 4001cb0ef41Sopenharmony_cifunction welcome(name) { 4011cb0ef41Sopenharmony_ci return `Hello ${name}!`; 4021cb0ef41Sopenharmony_ci} 4031cb0ef41Sopenharmony_ci 4041cb0ef41Sopenharmony_ciwelcome('Node.js User'); 4051cb0ef41Sopenharmony_ci 4061cb0ef41Sopenharmony_ci// ^D 4071cb0ef41Sopenharmony_ci'Hello Node.js User!' 4081cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">></span></code> <button class="copy-button">copy</button></pre> 4091cb0ef41Sopenharmony_ci<p>The following key combinations in the REPL have these special effects:</p> 4101cb0ef41Sopenharmony_ci<ul> 4111cb0ef41Sopenharmony_ci<li><kbd>Ctrl</kbd>+<kbd>C</kbd>: When pressed once, has the same effect as the 4121cb0ef41Sopenharmony_ci<code>.break</code> command. 4131cb0ef41Sopenharmony_ciWhen pressed twice on a blank line, has the same effect as the <code>.exit</code> 4141cb0ef41Sopenharmony_cicommand.</li> 4151cb0ef41Sopenharmony_ci<li><kbd>Ctrl</kbd>+<kbd>D</kbd>: Has the same effect as the <code>.exit</code> command.</li> 4161cb0ef41Sopenharmony_ci<li><kbd>Tab</kbd>: When pressed on a blank line, displays global and local 4171cb0ef41Sopenharmony_ci(scope) variables. When pressed while entering other input, displays relevant 4181cb0ef41Sopenharmony_ciautocompletion options.</li> 4191cb0ef41Sopenharmony_ci</ul> 4201cb0ef41Sopenharmony_ci<p>For key bindings related to the reverse-i-search, see <a href="#reverse-i-search"><code>reverse-i-search</code></a>. 4211cb0ef41Sopenharmony_ciFor all other key bindings, see <a href="readline.html#tty-keybindings">TTY keybindings</a>.</p> 4221cb0ef41Sopenharmony_ci<h4>Default evaluation<span><a class="mark" href="#default-evaluation" id="default-evaluation">#</a></span><a aria-hidden="true" class="legacy" id="repl_default_evaluation"></a></h4> 4231cb0ef41Sopenharmony_ci<p>By default, all instances of <a href="#class-replserver"><code>repl.REPLServer</code></a> use an evaluation function 4241cb0ef41Sopenharmony_cithat evaluates JavaScript expressions and provides access to Node.js built-in 4251cb0ef41Sopenharmony_cimodules. This default behavior can be overridden by passing in an alternative 4261cb0ef41Sopenharmony_cievaluation function when the <a href="#class-replserver"><code>repl.REPLServer</code></a> instance is created.</p> 4271cb0ef41Sopenharmony_ci<h5>JavaScript expressions<span><a class="mark" href="#javascript-expressions" id="javascript-expressions">#</a></span><a aria-hidden="true" class="legacy" id="repl_javascript_expressions"></a></h5> 4281cb0ef41Sopenharmony_ci<p>The default evaluator supports direct evaluation of JavaScript expressions:</p> 4291cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash">1 + 1</span> 4301cb0ef41Sopenharmony_ci2 4311cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">const m = 2</span> 4321cb0ef41Sopenharmony_ciundefined 4331cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">m + 1</span> 4341cb0ef41Sopenharmony_ci3</code> <button class="copy-button">copy</button></pre> 4351cb0ef41Sopenharmony_ci<p>Unless otherwise scoped within blocks or functions, variables declared 4361cb0ef41Sopenharmony_cieither implicitly or using the <code>const</code>, <code>let</code>, or <code>var</code> keywords 4371cb0ef41Sopenharmony_ciare declared at the global scope.</p> 4381cb0ef41Sopenharmony_ci<h5>Global and local scope<span><a class="mark" href="#global-and-local-scope" id="global-and-local-scope">#</a></span><a aria-hidden="true" class="legacy" id="repl_global_and_local_scope"></a></h5> 4391cb0ef41Sopenharmony_ci<p>The default evaluator provides access to any variables that exist in the global 4401cb0ef41Sopenharmony_ciscope. It is possible to expose a variable to the REPL explicitly by assigning 4411cb0ef41Sopenharmony_ciit to the <code>context</code> object associated with each <code>REPLServer</code>:</p> 4421cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> repl = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:repl'</span>); 4431cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> msg = <span class="hljs-string">'message'</span>; 4441cb0ef41Sopenharmony_ci 4451cb0ef41Sopenharmony_cirepl.<span class="hljs-title function_">start</span>(<span class="hljs-string">'> '</span>).<span class="hljs-property">context</span>.<span class="hljs-property">m</span> = msg;</code> <button class="copy-button">copy</button></pre> 4461cb0ef41Sopenharmony_ci<p>Properties in the <code>context</code> object appear as local within the REPL:</p> 4471cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">$ </span><span class="language-bash">node repl_test.js</span> 4481cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">m</span> 4491cb0ef41Sopenharmony_ci'message'</code> <button class="copy-button">copy</button></pre> 4501cb0ef41Sopenharmony_ci<p>Context properties are not read-only by default. To specify read-only globals, 4511cb0ef41Sopenharmony_cicontext properties must be defined using <code>Object.defineProperty()</code>:</p> 4521cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> repl = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:repl'</span>); 4531cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> msg = <span class="hljs-string">'message'</span>; 4541cb0ef41Sopenharmony_ci 4551cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> r = repl.<span class="hljs-title function_">start</span>(<span class="hljs-string">'> '</span>); 4561cb0ef41Sopenharmony_ci<span class="hljs-title class_">Object</span>.<span class="hljs-title function_">defineProperty</span>(r.<span class="hljs-property">context</span>, <span class="hljs-string">'m'</span>, { 4571cb0ef41Sopenharmony_ci <span class="hljs-attr">configurable</span>: <span class="hljs-literal">false</span>, 4581cb0ef41Sopenharmony_ci <span class="hljs-attr">enumerable</span>: <span class="hljs-literal">true</span>, 4591cb0ef41Sopenharmony_ci <span class="hljs-attr">value</span>: msg, 4601cb0ef41Sopenharmony_ci});</code> <button class="copy-button">copy</button></pre> 4611cb0ef41Sopenharmony_ci<h5>Accessing core Node.js modules<span><a class="mark" href="#accessing-core-nodejs-modules" id="accessing-core-nodejs-modules">#</a></span><a aria-hidden="true" class="legacy" id="repl_accessing_core_node_js_modules"></a></h5> 4621cb0ef41Sopenharmony_ci<p>The default evaluator will automatically load Node.js core modules into the 4631cb0ef41Sopenharmony_ciREPL environment when used. For instance, unless otherwise declared as a 4641cb0ef41Sopenharmony_ciglobal or scoped variable, the input <code>fs</code> will be evaluated on-demand as 4651cb0ef41Sopenharmony_ci<code>global.fs = require('node:fs')</code>.</p> 4661cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash">fs.createReadStream(<span class="hljs-string">'./some/file'</span>);</span></code> <button class="copy-button">copy</button></pre> 4671cb0ef41Sopenharmony_ci<h5>Global uncaught exceptions<span><a class="mark" href="#global-uncaught-exceptions" id="global-uncaught-exceptions">#</a></span><a aria-hidden="true" class="legacy" id="repl_global_uncaught_exceptions"></a></h5> 4681cb0ef41Sopenharmony_ci<div class="api_metadata"> 4691cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 4701cb0ef41Sopenharmony_ci<table> 4711cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 4721cb0ef41Sopenharmony_ci<tr><td>v12.3.0</td> 4731cb0ef41Sopenharmony_ci<td><p>The <code>'uncaughtException'</code> event is from now on triggered if the repl is used as standalone program.</p></td></tr> 4741cb0ef41Sopenharmony_ci</tbody></table> 4751cb0ef41Sopenharmony_ci</details> 4761cb0ef41Sopenharmony_ci</div> 4771cb0ef41Sopenharmony_ci<p>The REPL uses the <a href="domain.html"><code>domain</code></a> module to catch all uncaught exceptions for that 4781cb0ef41Sopenharmony_ciREPL session.</p> 4791cb0ef41Sopenharmony_ci<p>This use of the <a href="domain.html"><code>domain</code></a> module in the REPL has these side effects:</p> 4801cb0ef41Sopenharmony_ci<ul> 4811cb0ef41Sopenharmony_ci<li> 4821cb0ef41Sopenharmony_ci<p>Uncaught exceptions only emit the <a href="process.html#event-uncaughtexception"><code>'uncaughtException'</code></a> event in the 4831cb0ef41Sopenharmony_cistandalone REPL. Adding a listener for this event in a REPL within 4841cb0ef41Sopenharmony_cianother Node.js program results in <a href="errors.html#err_invalid_repl_input"><code>ERR_INVALID_REPL_INPUT</code></a>.</p> 4851cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> r = repl.<span class="hljs-title function_">start</span>(); 4861cb0ef41Sopenharmony_ci 4871cb0ef41Sopenharmony_cir.<span class="hljs-title function_">write</span>(<span class="hljs-string">'process.on("uncaughtException", () => console.log("Foobar"));\n'</span>); 4881cb0ef41Sopenharmony_ci<span class="hljs-comment">// Output stream includes:</span> 4891cb0ef41Sopenharmony_ci<span class="hljs-comment">// TypeError [ERR_INVALID_REPL_INPUT]: Listeners for `uncaughtException`</span> 4901cb0ef41Sopenharmony_ci<span class="hljs-comment">// cannot be used in the REPL</span> 4911cb0ef41Sopenharmony_ci 4921cb0ef41Sopenharmony_cir.<span class="hljs-title function_">close</span>();</code> <button class="copy-button">copy</button></pre> 4931cb0ef41Sopenharmony_ci</li> 4941cb0ef41Sopenharmony_ci<li> 4951cb0ef41Sopenharmony_ci<p>Trying to use <a href="process.html#processsetuncaughtexceptioncapturecallbackfn"><code>process.setUncaughtExceptionCaptureCallback()</code></a> throws 4961cb0ef41Sopenharmony_cian <a href="errors.html#err_domain_cannot_set_uncaught_exception_capture"><code>ERR_DOMAIN_CANNOT_SET_UNCAUGHT_EXCEPTION_CAPTURE</code></a> error.</p> 4971cb0ef41Sopenharmony_ci</li> 4981cb0ef41Sopenharmony_ci</ul> 4991cb0ef41Sopenharmony_ci<h5>Assignment of the <code>_</code> (underscore) variable<span><a class="mark" href="#assignment-of-the-_-underscore-variable" id="assignment-of-the-_-underscore-variable">#</a></span><a aria-hidden="true" class="legacy" id="repl_assignment_of_the_underscore_variable"></a></h5> 5001cb0ef41Sopenharmony_ci<div class="api_metadata"> 5011cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 5021cb0ef41Sopenharmony_ci<table> 5031cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 5041cb0ef41Sopenharmony_ci<tr><td>v9.8.0</td> 5051cb0ef41Sopenharmony_ci<td><p>Added <code>_error</code> support.</p></td></tr> 5061cb0ef41Sopenharmony_ci</tbody></table> 5071cb0ef41Sopenharmony_ci</details> 5081cb0ef41Sopenharmony_ci</div> 5091cb0ef41Sopenharmony_ci<p>The default evaluator will, by default, assign the result of the most recently 5101cb0ef41Sopenharmony_cievaluated expression to the special variable <code>_</code> (underscore). 5111cb0ef41Sopenharmony_ciExplicitly setting <code>_</code> to a value will disable this behavior.</p> 5121cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash">[ <span class="hljs-string">'a'</span>, <span class="hljs-string">'b'</span>, <span class="hljs-string">'c'</span> ]</span> 5131cb0ef41Sopenharmony_ci[ 'a', 'b', 'c' ] 5141cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">_.length</span> 5151cb0ef41Sopenharmony_ci3 5161cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">_ += 1</span> 5171cb0ef41Sopenharmony_ciExpression assignment to _ now disabled. 5181cb0ef41Sopenharmony_ci4 5191cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">1 + 1</span> 5201cb0ef41Sopenharmony_ci2 5211cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">_</span> 5221cb0ef41Sopenharmony_ci4</code> <button class="copy-button">copy</button></pre> 5231cb0ef41Sopenharmony_ci<p>Similarly, <code>_error</code> will refer to the last seen error, if there was any. 5241cb0ef41Sopenharmony_ciExplicitly setting <code>_error</code> to a value will disable this behavior.</p> 5251cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash">throw new Error(<span class="hljs-string">'foo'</span>);</span> 5261cb0ef41Sopenharmony_ciUncaught Error: foo 5271cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">_error.message</span> 5281cb0ef41Sopenharmony_ci'foo'</code> <button class="copy-button">copy</button></pre> 5291cb0ef41Sopenharmony_ci<h5><code>await</code> keyword<span><a class="mark" href="#await-keyword" id="await-keyword">#</a></span><a aria-hidden="true" class="legacy" id="repl_await_keyword"></a></h5> 5301cb0ef41Sopenharmony_ci<p>Support for the <code>await</code> keyword is enabled at the top level.</p> 5311cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash">await Promise.resolve(123)</span> 5321cb0ef41Sopenharmony_ci123 5331cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">await Promise.reject(new Error(<span class="hljs-string">'REPL await'</span>))</span> 5341cb0ef41Sopenharmony_ciUncaught Error: REPL await 5351cb0ef41Sopenharmony_ci at REPL2:1:54 5361cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">const <span class="hljs-built_in">timeout</span> = util.promisify(setTimeout);</span> 5371cb0ef41Sopenharmony_ciundefined 5381cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">const old = Date.now(); await <span class="hljs-built_in">timeout</span>(1000); console.log(Date.now() - old);</span> 5391cb0ef41Sopenharmony_ci1002 5401cb0ef41Sopenharmony_ciundefined</code> <button class="copy-button">copy</button></pre> 5411cb0ef41Sopenharmony_ci<p>One known limitation of using the <code>await</code> keyword in the REPL is that 5421cb0ef41Sopenharmony_ciit will invalidate the lexical scoping of the <code>const</code> and <code>let</code> 5431cb0ef41Sopenharmony_cikeywords.</p> 5441cb0ef41Sopenharmony_ci<p>For example:</p> 5451cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash">const m = await Promise.resolve(123)</span> 5461cb0ef41Sopenharmony_ciundefined 5471cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">m</span> 5481cb0ef41Sopenharmony_ci123 5491cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">const m = await Promise.resolve(234)</span> 5501cb0ef41Sopenharmony_ciundefined 5511cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">m</span> 5521cb0ef41Sopenharmony_ci234</code> <button class="copy-button">copy</button></pre> 5531cb0ef41Sopenharmony_ci<p><a href="cli.html#--no-experimental-repl-await"><code>--no-experimental-repl-await</code></a> shall disable top-level await in REPL.</p> 5541cb0ef41Sopenharmony_ci<h4>Reverse-i-search<span><a class="mark" href="#reverse-i-search" id="reverse-i-search">#</a></span><a aria-hidden="true" class="legacy" id="repl_reverse_i_search"></a></h4> 5551cb0ef41Sopenharmony_ci<div class="api_metadata"> 5561cb0ef41Sopenharmony_ci<span>Added in: v13.6.0, v12.17.0</span> 5571cb0ef41Sopenharmony_ci</div> 5581cb0ef41Sopenharmony_ci<p>The REPL supports bi-directional reverse-i-search similar to <a href="https://en.wikipedia.org/wiki/Z_shell">ZSH</a>. It is 5591cb0ef41Sopenharmony_citriggered with <kbd>Ctrl</kbd>+<kbd>R</kbd> to search backward 5601cb0ef41Sopenharmony_ciand <kbd>Ctrl</kbd>+<kbd>S</kbd> to search forwards.</p> 5611cb0ef41Sopenharmony_ci<p>Duplicated history entries will be skipped.</p> 5621cb0ef41Sopenharmony_ci<p>Entries are accepted as soon as any key is pressed that doesn't correspond 5631cb0ef41Sopenharmony_ciwith the reverse search. Cancelling is possible by pressing <kbd>Esc</kbd> 5641cb0ef41Sopenharmony_cior <kbd>Ctrl</kbd>+<kbd>C</kbd>.</p> 5651cb0ef41Sopenharmony_ci<p>Changing the direction immediately searches for the next entry in the expected 5661cb0ef41Sopenharmony_cidirection from the current position on.</p> 5671cb0ef41Sopenharmony_ci<h4>Custom evaluation functions<span><a class="mark" href="#custom-evaluation-functions" id="custom-evaluation-functions">#</a></span><a aria-hidden="true" class="legacy" id="repl_custom_evaluation_functions"></a></h4> 5681cb0ef41Sopenharmony_ci<p>When a new <a href="#class-replserver"><code>repl.REPLServer</code></a> is created, a custom evaluation function may be 5691cb0ef41Sopenharmony_ciprovided. This can be used, for instance, to implement fully customized REPL 5701cb0ef41Sopenharmony_ciapplications.</p> 5711cb0ef41Sopenharmony_ci<p>The following illustrates a hypothetical example of a REPL that performs 5721cb0ef41Sopenharmony_citranslation of text from one language to another:</p> 5731cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> repl = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:repl'</span>); 5741cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> { <span class="hljs-title class_">Translator</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'translator'</span>); 5751cb0ef41Sopenharmony_ci 5761cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> myTranslator = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Translator</span>(<span class="hljs-string">'en'</span>, <span class="hljs-string">'fr'</span>); 5771cb0ef41Sopenharmony_ci 5781cb0ef41Sopenharmony_ci<span class="hljs-keyword">function</span> <span class="hljs-title function_">myEval</span>(<span class="hljs-params">cmd, context, filename, callback</span>) { 5791cb0ef41Sopenharmony_ci <span class="hljs-title function_">callback</span>(<span class="hljs-literal">null</span>, myTranslator.<span class="hljs-title function_">translate</span>(cmd)); 5801cb0ef41Sopenharmony_ci} 5811cb0ef41Sopenharmony_ci 5821cb0ef41Sopenharmony_cirepl.<span class="hljs-title function_">start</span>({ <span class="hljs-attr">prompt</span>: <span class="hljs-string">'> '</span>, <span class="hljs-attr">eval</span>: myEval });</code> <button class="copy-button">copy</button></pre> 5831cb0ef41Sopenharmony_ci<h5>Recoverable errors<span><a class="mark" href="#recoverable-errors" id="recoverable-errors">#</a></span><a aria-hidden="true" class="legacy" id="repl_recoverable_errors"></a></h5> 5841cb0ef41Sopenharmony_ci<p>At the REPL prompt, pressing <kbd>Enter</kbd> sends the current line of input to 5851cb0ef41Sopenharmony_cithe <code>eval</code> function. In order to support multi-line input, the <code>eval</code> function 5861cb0ef41Sopenharmony_cican return an instance of <code>repl.Recoverable</code> to the provided callback function:</p> 5871cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">function</span> <span class="hljs-title function_">myEval</span>(<span class="hljs-params">cmd, context, filename, callback</span>) { 5881cb0ef41Sopenharmony_ci <span class="hljs-keyword">let</span> result; 5891cb0ef41Sopenharmony_ci <span class="hljs-keyword">try</span> { 5901cb0ef41Sopenharmony_ci result = vm.<span class="hljs-title function_">runInThisContext</span>(cmd); 5911cb0ef41Sopenharmony_ci } <span class="hljs-keyword">catch</span> (e) { 5921cb0ef41Sopenharmony_ci <span class="hljs-keyword">if</span> (<span class="hljs-title function_">isRecoverableError</span>(e)) { 5931cb0ef41Sopenharmony_ci <span class="hljs-keyword">return</span> <span class="hljs-title function_">callback</span>(<span class="hljs-keyword">new</span> repl.<span class="hljs-title class_">Recoverable</span>(e)); 5941cb0ef41Sopenharmony_ci } 5951cb0ef41Sopenharmony_ci } 5961cb0ef41Sopenharmony_ci <span class="hljs-title function_">callback</span>(<span class="hljs-literal">null</span>, result); 5971cb0ef41Sopenharmony_ci} 5981cb0ef41Sopenharmony_ci 5991cb0ef41Sopenharmony_ci<span class="hljs-keyword">function</span> <span class="hljs-title function_">isRecoverableError</span>(<span class="hljs-params">error</span>) { 6001cb0ef41Sopenharmony_ci <span class="hljs-keyword">if</span> (error.<span class="hljs-property">name</span> === <span class="hljs-string">'SyntaxError'</span>) { 6011cb0ef41Sopenharmony_ci <span class="hljs-keyword">return</span> <span class="hljs-regexp">/^(Unexpected end of input|Unexpected token)/</span>.<span class="hljs-title function_">test</span>(error.<span class="hljs-property">message</span>); 6021cb0ef41Sopenharmony_ci } 6031cb0ef41Sopenharmony_ci <span class="hljs-keyword">return</span> <span class="hljs-literal">false</span>; 6041cb0ef41Sopenharmony_ci}</code> <button class="copy-button">copy</button></pre> 6051cb0ef41Sopenharmony_ci<h4>Customizing REPL output<span><a class="mark" href="#customizing-repl-output" id="customizing-repl-output">#</a></span><a aria-hidden="true" class="legacy" id="repl_customizing_repl_output"></a></h4> 6061cb0ef41Sopenharmony_ci<p>By default, <a href="#class-replserver"><code>repl.REPLServer</code></a> instances format output using the 6071cb0ef41Sopenharmony_ci<a href="util.html#utilinspectobject-options"><code>util.inspect()</code></a> method before writing the output to the provided <code>Writable</code> 6081cb0ef41Sopenharmony_cistream (<code>process.stdout</code> by default). The <code>showProxy</code> inspection option is set 6091cb0ef41Sopenharmony_cito true by default and the <code>colors</code> option is set to true depending on the 6101cb0ef41Sopenharmony_ciREPL's <code>useColors</code> option.</p> 6111cb0ef41Sopenharmony_ci<p>The <code>useColors</code> boolean option can be specified at construction to instruct the 6121cb0ef41Sopenharmony_cidefault writer to use ANSI style codes to colorize the output from the 6131cb0ef41Sopenharmony_ci<code>util.inspect()</code> method.</p> 6141cb0ef41Sopenharmony_ci<p>If the REPL is run as standalone program, it is also possible to change the 6151cb0ef41Sopenharmony_ciREPL's <a href="util.html#utilinspectobject-options">inspection defaults</a> from inside the REPL by using the 6161cb0ef41Sopenharmony_ci<code>inspect.replDefaults</code> property which mirrors the <code>defaultOptions</code> from 6171cb0ef41Sopenharmony_ci<a href="util.html#utilinspectobject-options"><code>util.inspect()</code></a>.</p> 6181cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash">util.inspect.replDefaults.compact = <span class="hljs-literal">false</span>;</span> 6191cb0ef41Sopenharmony_cifalse 6201cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">[1]</span> 6211cb0ef41Sopenharmony_ci[ 6221cb0ef41Sopenharmony_ci 1 6231cb0ef41Sopenharmony_ci] 6241cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">></span></code> <button class="copy-button">copy</button></pre> 6251cb0ef41Sopenharmony_ci<p>To fully customize the output of a <a href="#class-replserver"><code>repl.REPLServer</code></a> instance pass in a new 6261cb0ef41Sopenharmony_cifunction for the <code>writer</code> option on construction. The following example, for 6271cb0ef41Sopenharmony_ciinstance, simply converts any input text to upper case:</p> 6281cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> repl = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:repl'</span>); 6291cb0ef41Sopenharmony_ci 6301cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> r = repl.<span class="hljs-title function_">start</span>({ <span class="hljs-attr">prompt</span>: <span class="hljs-string">'> '</span>, <span class="hljs-attr">eval</span>: myEval, <span class="hljs-attr">writer</span>: myWriter }); 6311cb0ef41Sopenharmony_ci 6321cb0ef41Sopenharmony_ci<span class="hljs-keyword">function</span> <span class="hljs-title function_">myEval</span>(<span class="hljs-params">cmd, context, filename, callback</span>) { 6331cb0ef41Sopenharmony_ci <span class="hljs-title function_">callback</span>(<span class="hljs-literal">null</span>, cmd); 6341cb0ef41Sopenharmony_ci} 6351cb0ef41Sopenharmony_ci 6361cb0ef41Sopenharmony_ci<span class="hljs-keyword">function</span> <span class="hljs-title function_">myWriter</span>(<span class="hljs-params">output</span>) { 6371cb0ef41Sopenharmony_ci <span class="hljs-keyword">return</span> output.<span class="hljs-title function_">toUpperCase</span>(); 6381cb0ef41Sopenharmony_ci}</code> <button class="copy-button">copy</button></pre> 6391cb0ef41Sopenharmony_ci</section><section><h3>Class: <code>REPLServer</code><span><a class="mark" href="#class-replserver" id="class-replserver">#</a></span><a aria-hidden="true" class="legacy" id="repl_class_replserver"></a></h3> 6401cb0ef41Sopenharmony_ci<div class="api_metadata"> 6411cb0ef41Sopenharmony_ci<span>Added in: v0.1.91</span> 6421cb0ef41Sopenharmony_ci</div> 6431cb0ef41Sopenharmony_ci<ul> 6441cb0ef41Sopenharmony_ci<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> See <a href="#replstartoptions"><code>repl.start()</code></a></li> 6451cb0ef41Sopenharmony_ci<li>Extends: <a href="readline.html#class-readlineinterface" class="type"><readline.Interface></a></li> 6461cb0ef41Sopenharmony_ci</ul> 6471cb0ef41Sopenharmony_ci<p>Instances of <code>repl.REPLServer</code> are created using the <a href="#replstartoptions"><code>repl.start()</code></a> method 6481cb0ef41Sopenharmony_cior directly using the JavaScript <code>new</code> keyword.</p> 6491cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> repl = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:repl'</span>); 6501cb0ef41Sopenharmony_ci 6511cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> options = { <span class="hljs-attr">useColors</span>: <span class="hljs-literal">true</span> }; 6521cb0ef41Sopenharmony_ci 6531cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> firstInstance = repl.<span class="hljs-title function_">start</span>(options); 6541cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> secondInstance = <span class="hljs-keyword">new</span> repl.<span class="hljs-title class_">REPLServer</span>(options);</code> <button class="copy-button">copy</button></pre> 6551cb0ef41Sopenharmony_ci<h4>Event: <code>'exit'</code><span><a class="mark" href="#event-exit" id="event-exit">#</a></span><a aria-hidden="true" class="legacy" id="repl_event_exit"></a></h4> 6561cb0ef41Sopenharmony_ci<div class="api_metadata"> 6571cb0ef41Sopenharmony_ci<span>Added in: v0.7.7</span> 6581cb0ef41Sopenharmony_ci</div> 6591cb0ef41Sopenharmony_ci<p>The <code>'exit'</code> event is emitted when the REPL is exited either by receiving the 6601cb0ef41Sopenharmony_ci<code>.exit</code> command as input, the user pressing <kbd>Ctrl</kbd>+<kbd>C</kbd> twice 6611cb0ef41Sopenharmony_cito signal <code>SIGINT</code>, 6621cb0ef41Sopenharmony_cior by pressing <kbd>Ctrl</kbd>+<kbd>D</kbd> to signal <code>'end'</code> on the input 6631cb0ef41Sopenharmony_cistream. The listener 6641cb0ef41Sopenharmony_cicallback is invoked without any arguments.</p> 6651cb0ef41Sopenharmony_ci<pre><code class="language-js">replServer.<span class="hljs-title function_">on</span>(<span class="hljs-string">'exit'</span>, <span class="hljs-function">() =></span> { 6661cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'Received "exit" event from repl!'</span>); 6671cb0ef41Sopenharmony_ci process.<span class="hljs-title function_">exit</span>(); 6681cb0ef41Sopenharmony_ci});</code> <button class="copy-button">copy</button></pre> 6691cb0ef41Sopenharmony_ci<h4>Event: <code>'reset'</code><span><a class="mark" href="#event-reset" id="event-reset">#</a></span><a aria-hidden="true" class="legacy" id="repl_event_reset"></a></h4> 6701cb0ef41Sopenharmony_ci<div class="api_metadata"> 6711cb0ef41Sopenharmony_ci<span>Added in: v0.11.0</span> 6721cb0ef41Sopenharmony_ci</div> 6731cb0ef41Sopenharmony_ci<p>The <code>'reset'</code> event is emitted when the REPL's context is reset. This occurs 6741cb0ef41Sopenharmony_ciwhenever the <code>.clear</code> command is received as input <em>unless</em> the REPL is using 6751cb0ef41Sopenharmony_cithe default evaluator and the <code>repl.REPLServer</code> instance was created with the 6761cb0ef41Sopenharmony_ci<code>useGlobal</code> option set to <code>true</code>. The listener callback will be called with a 6771cb0ef41Sopenharmony_cireference to the <code>context</code> object as the only argument.</p> 6781cb0ef41Sopenharmony_ci<p>This can be used primarily to re-initialize REPL context to some pre-defined 6791cb0ef41Sopenharmony_cistate:</p> 6801cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> repl = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:repl'</span>); 6811cb0ef41Sopenharmony_ci 6821cb0ef41Sopenharmony_ci<span class="hljs-keyword">function</span> <span class="hljs-title function_">initializeContext</span>(<span class="hljs-params">context</span>) { 6831cb0ef41Sopenharmony_ci context.<span class="hljs-property">m</span> = <span class="hljs-string">'test'</span>; 6841cb0ef41Sopenharmony_ci} 6851cb0ef41Sopenharmony_ci 6861cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> r = repl.<span class="hljs-title function_">start</span>({ <span class="hljs-attr">prompt</span>: <span class="hljs-string">'> '</span> }); 6871cb0ef41Sopenharmony_ci<span class="hljs-title function_">initializeContext</span>(r.<span class="hljs-property">context</span>); 6881cb0ef41Sopenharmony_ci 6891cb0ef41Sopenharmony_cir.<span class="hljs-title function_">on</span>(<span class="hljs-string">'reset'</span>, initializeContext);</code> <button class="copy-button">copy</button></pre> 6901cb0ef41Sopenharmony_ci<p>When this code is executed, the global <code>'m'</code> variable can be modified but then 6911cb0ef41Sopenharmony_cireset to its initial value using the <code>.clear</code> command:</p> 6921cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">$ </span><span class="language-bash">./node example.js</span> 6931cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">m</span> 6941cb0ef41Sopenharmony_ci'test' 6951cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">m = 1</span> 6961cb0ef41Sopenharmony_ci1 6971cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">m</span> 6981cb0ef41Sopenharmony_ci1 6991cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">.clear</span> 7001cb0ef41Sopenharmony_ciClearing context... 7011cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">m</span> 7021cb0ef41Sopenharmony_ci'test' 7031cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">></span></code> <button class="copy-button">copy</button></pre> 7041cb0ef41Sopenharmony_ci<h4><code>replServer.defineCommand(keyword, cmd)</code><span><a class="mark" href="#replserverdefinecommandkeyword-cmd" id="replserverdefinecommandkeyword-cmd">#</a></span><a aria-hidden="true" class="legacy" id="repl_replserver_definecommand_keyword_cmd"></a></h4> 7051cb0ef41Sopenharmony_ci<div class="api_metadata"> 7061cb0ef41Sopenharmony_ci<span>Added in: v0.3.0</span> 7071cb0ef41Sopenharmony_ci</div> 7081cb0ef41Sopenharmony_ci<ul> 7091cb0ef41Sopenharmony_ci<li><code>keyword</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The command keyword (<em>without</em> a leading <code>.</code> character).</li> 7101cb0ef41Sopenharmony_ci<li><code>cmd</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> The function to invoke when the command is processed.</li> 7111cb0ef41Sopenharmony_ci</ul> 7121cb0ef41Sopenharmony_ci<p>The <code>replServer.defineCommand()</code> method is used to add new <code>.</code>-prefixed commands 7131cb0ef41Sopenharmony_cito the REPL instance. Such commands are invoked by typing a <code>.</code> followed by the 7141cb0ef41Sopenharmony_ci<code>keyword</code>. The <code>cmd</code> is either a <code>Function</code> or an <code>Object</code> with the following 7151cb0ef41Sopenharmony_ciproperties:</p> 7161cb0ef41Sopenharmony_ci<ul> 7171cb0ef41Sopenharmony_ci<li><code>help</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> Help text to be displayed when <code>.help</code> is entered (Optional).</li> 7181cb0ef41Sopenharmony_ci<li><code>action</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> The function to execute, optionally accepting a single 7191cb0ef41Sopenharmony_cistring argument.</li> 7201cb0ef41Sopenharmony_ci</ul> 7211cb0ef41Sopenharmony_ci<p>The following example shows two new commands added to the REPL instance:</p> 7221cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> repl = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:repl'</span>); 7231cb0ef41Sopenharmony_ci 7241cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> replServer = repl.<span class="hljs-title function_">start</span>({ <span class="hljs-attr">prompt</span>: <span class="hljs-string">'> '</span> }); 7251cb0ef41Sopenharmony_cireplServer.<span class="hljs-title function_">defineCommand</span>(<span class="hljs-string">'sayhello'</span>, { 7261cb0ef41Sopenharmony_ci <span class="hljs-attr">help</span>: <span class="hljs-string">'Say hello'</span>, 7271cb0ef41Sopenharmony_ci <span class="hljs-title function_">action</span>(<span class="hljs-params">name</span>) { 7281cb0ef41Sopenharmony_ci <span class="hljs-variable language_">this</span>.<span class="hljs-title function_">clearBufferedCommand</span>(); 7291cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`Hello, <span class="hljs-subst">${name}</span>!`</span>); 7301cb0ef41Sopenharmony_ci <span class="hljs-variable language_">this</span>.<span class="hljs-title function_">displayPrompt</span>(); 7311cb0ef41Sopenharmony_ci }, 7321cb0ef41Sopenharmony_ci}); 7331cb0ef41Sopenharmony_cireplServer.<span class="hljs-title function_">defineCommand</span>(<span class="hljs-string">'saybye'</span>, <span class="hljs-keyword">function</span> <span class="hljs-title function_">saybye</span>(<span class="hljs-params"></span>) { 7341cb0ef41Sopenharmony_ci <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'Goodbye!'</span>); 7351cb0ef41Sopenharmony_ci <span class="hljs-variable language_">this</span>.<span class="hljs-title function_">close</span>(); 7361cb0ef41Sopenharmony_ci});</code> <button class="copy-button">copy</button></pre> 7371cb0ef41Sopenharmony_ci<p>The new commands can then be used from within the REPL instance:</p> 7381cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash">.sayhello Node.js User</span> 7391cb0ef41Sopenharmony_ciHello, Node.js User! 7401cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">.saybye</span> 7411cb0ef41Sopenharmony_ciGoodbye!</code> <button class="copy-button">copy</button></pre> 7421cb0ef41Sopenharmony_ci<h4><code>replServer.displayPrompt([preserveCursor])</code><span><a class="mark" href="#replserverdisplaypromptpreservecursor" id="replserverdisplaypromptpreservecursor">#</a></span><a aria-hidden="true" class="legacy" id="repl_replserver_displayprompt_preservecursor"></a></h4> 7431cb0ef41Sopenharmony_ci<div class="api_metadata"> 7441cb0ef41Sopenharmony_ci<span>Added in: v0.1.91</span> 7451cb0ef41Sopenharmony_ci</div> 7461cb0ef41Sopenharmony_ci<ul> 7471cb0ef41Sopenharmony_ci<li><code>preserveCursor</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 7481cb0ef41Sopenharmony_ci</ul> 7491cb0ef41Sopenharmony_ci<p>The <code>replServer.displayPrompt()</code> method readies the REPL instance for input 7501cb0ef41Sopenharmony_cifrom the user, printing the configured <code>prompt</code> to a new line in the <code>output</code> 7511cb0ef41Sopenharmony_ciand resuming the <code>input</code> to accept new input.</p> 7521cb0ef41Sopenharmony_ci<p>When multi-line input is being entered, an ellipsis is printed rather than the 7531cb0ef41Sopenharmony_ci'prompt'.</p> 7541cb0ef41Sopenharmony_ci<p>When <code>preserveCursor</code> is <code>true</code>, the cursor placement will not be reset to <code>0</code>.</p> 7551cb0ef41Sopenharmony_ci<p>The <code>replServer.displayPrompt</code> method is primarily intended to be called from 7561cb0ef41Sopenharmony_ciwithin the action function for commands registered using the 7571cb0ef41Sopenharmony_ci<code>replServer.defineCommand()</code> method.</p> 7581cb0ef41Sopenharmony_ci<h4><code>replServer.clearBufferedCommand()</code><span><a class="mark" href="#replserverclearbufferedcommand" id="replserverclearbufferedcommand">#</a></span><a aria-hidden="true" class="legacy" id="repl_replserver_clearbufferedcommand"></a></h4> 7591cb0ef41Sopenharmony_ci<div class="api_metadata"> 7601cb0ef41Sopenharmony_ci<span>Added in: v9.0.0</span> 7611cb0ef41Sopenharmony_ci</div> 7621cb0ef41Sopenharmony_ci<p>The <code>replServer.clearBufferedCommand()</code> method clears any command that has been 7631cb0ef41Sopenharmony_cibuffered but not yet executed. This method is primarily intended to be 7641cb0ef41Sopenharmony_cicalled from within the action function for commands registered using the 7651cb0ef41Sopenharmony_ci<code>replServer.defineCommand()</code> method.</p> 7661cb0ef41Sopenharmony_ci<h4><code>replServer.parseREPLKeyword(keyword[, rest])</code><span><a class="mark" href="#replserverparsereplkeywordkeyword-rest" id="replserverparsereplkeywordkeyword-rest">#</a></span><a aria-hidden="true" class="legacy" id="repl_replserver_parsereplkeyword_keyword_rest"></a></h4> 7671cb0ef41Sopenharmony_ci<div class="api_metadata"> 7681cb0ef41Sopenharmony_ci<span>Added in: v0.8.9</span><span>Deprecated since: v9.0.0</span> 7691cb0ef41Sopenharmony_ci</div> 7701cb0ef41Sopenharmony_ci<p></p><div class="api_stability api_stability_0"><a href="documentation.html#stability-index">Stability: 0</a> - Deprecated.</div><p></p> 7711cb0ef41Sopenharmony_ci<ul> 7721cb0ef41Sopenharmony_ci<li><code>keyword</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> the potential keyword to parse and execute</li> 7731cb0ef41Sopenharmony_ci<li><code>rest</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type"><any></a> any parameters to the keyword command</li> 7741cb0ef41Sopenharmony_ci<li>Returns: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a></li> 7751cb0ef41Sopenharmony_ci</ul> 7761cb0ef41Sopenharmony_ci<p>An internal method used to parse and execute <code>REPLServer</code> keywords. 7771cb0ef41Sopenharmony_ciReturns <code>true</code> if <code>keyword</code> is a valid keyword, otherwise <code>false</code>.</p> 7781cb0ef41Sopenharmony_ci<h4><code>replServer.setupHistory(historyPath, callback)</code><span><a class="mark" href="#replserversetuphistoryhistorypath-callback" id="replserversetuphistoryhistorypath-callback">#</a></span><a aria-hidden="true" class="legacy" id="repl_replserver_setuphistory_historypath_callback"></a></h4> 7791cb0ef41Sopenharmony_ci<div class="api_metadata"> 7801cb0ef41Sopenharmony_ci<span>Added in: v11.10.0</span> 7811cb0ef41Sopenharmony_ci</div> 7821cb0ef41Sopenharmony_ci<ul> 7831cb0ef41Sopenharmony_ci<li><code>historyPath</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> the path to the history file</li> 7841cb0ef41Sopenharmony_ci<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> called when history writes are ready or upon error 7851cb0ef41Sopenharmony_ci<ul> 7861cb0ef41Sopenharmony_ci<li><code>err</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error" class="type"><Error></a></li> 7871cb0ef41Sopenharmony_ci<li><code>repl</code> <a href="repl.html#class-replserver" class="type"><repl.REPLServer></a></li> 7881cb0ef41Sopenharmony_ci</ul> 7891cb0ef41Sopenharmony_ci</li> 7901cb0ef41Sopenharmony_ci</ul> 7911cb0ef41Sopenharmony_ci<p>Initializes a history log file for the REPL instance. When executing the 7921cb0ef41Sopenharmony_ciNode.js binary and using the command-line REPL, a history file is initialized 7931cb0ef41Sopenharmony_ciby default. However, this is not the case when creating a REPL 7941cb0ef41Sopenharmony_ciprogrammatically. Use this method to initialize a history log file when working 7951cb0ef41Sopenharmony_ciwith REPL instances programmatically.</p> 7961cb0ef41Sopenharmony_ci</section><section><h3><code>repl.builtinModules</code><span><a class="mark" href="#replbuiltinmodules" id="replbuiltinmodules">#</a></span><a aria-hidden="true" class="legacy" id="repl_repl_builtinmodules"></a></h3> 7971cb0ef41Sopenharmony_ci<div class="api_metadata"> 7981cb0ef41Sopenharmony_ci<span>Added in: v14.5.0</span> 7991cb0ef41Sopenharmony_ci</div> 8001cb0ef41Sopenharmony_ci<ul> 8011cb0ef41Sopenharmony_ci<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string[]></a></li> 8021cb0ef41Sopenharmony_ci</ul> 8031cb0ef41Sopenharmony_ci<p>A list of the names of all Node.js modules, e.g., <code>'http'</code>.</p> 8041cb0ef41Sopenharmony_ci</section><section><h3><code>repl.start([options])</code><span><a class="mark" href="#replstartoptions" id="replstartoptions">#</a></span><a aria-hidden="true" class="legacy" id="repl_repl_start_options"></a></h3> 8051cb0ef41Sopenharmony_ci<div class="api_metadata"> 8061cb0ef41Sopenharmony_ci<details class="changelog"><summary>History</summary> 8071cb0ef41Sopenharmony_ci<table> 8081cb0ef41Sopenharmony_ci<tbody><tr><th>Version</th><th>Changes</th></tr> 8091cb0ef41Sopenharmony_ci<tr><td>v13.4.0, v12.17.0</td> 8101cb0ef41Sopenharmony_ci<td><p>The <code>preview</code> option is now available.</p></td></tr> 8111cb0ef41Sopenharmony_ci<tr><td>v12.0.0</td> 8121cb0ef41Sopenharmony_ci<td><p>The <code>terminal</code> option now follows the default description in all cases and <code>useColors</code> checks <code>hasColors()</code> if available.</p></td></tr> 8131cb0ef41Sopenharmony_ci<tr><td>v10.0.0</td> 8141cb0ef41Sopenharmony_ci<td><p>The <code>REPL_MAGIC_MODE</code> <code>replMode</code> was removed.</p></td></tr> 8151cb0ef41Sopenharmony_ci<tr><td>v6.3.0</td> 8161cb0ef41Sopenharmony_ci<td><p>The <code>breakEvalOnSigint</code> option is supported now.</p></td></tr> 8171cb0ef41Sopenharmony_ci<tr><td>v5.8.0</td> 8181cb0ef41Sopenharmony_ci<td><p>The <code>options</code> parameter is optional now.</p></td></tr> 8191cb0ef41Sopenharmony_ci<tr><td>v0.1.91</td> 8201cb0ef41Sopenharmony_ci<td><p><span>Added in: v0.1.91</span></p></td></tr> 8211cb0ef41Sopenharmony_ci</tbody></table> 8221cb0ef41Sopenharmony_ci</details> 8231cb0ef41Sopenharmony_ci</div> 8241cb0ef41Sopenharmony_ci<ul> 8251cb0ef41Sopenharmony_ci<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type"><Object></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> 8261cb0ef41Sopenharmony_ci<ul> 8271cb0ef41Sopenharmony_ci<li><code>prompt</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type"><string></a> The input prompt to display. <strong>Default:</strong> <code>'> '</code> 8281cb0ef41Sopenharmony_ci(with a trailing space).</li> 8291cb0ef41Sopenharmony_ci<li><code>input</code> <a href="stream.html#class-streamreadable" class="type"><stream.Readable></a> The <code>Readable</code> stream from which REPL input will 8301cb0ef41Sopenharmony_cibe read. <strong>Default:</strong> <code>process.stdin</code>.</li> 8311cb0ef41Sopenharmony_ci<li><code>output</code> <a href="stream.html#class-streamwritable" class="type"><stream.Writable></a> The <code>Writable</code> stream to which REPL output will 8321cb0ef41Sopenharmony_cibe written. <strong>Default:</strong> <code>process.stdout</code>.</li> 8331cb0ef41Sopenharmony_ci<li><code>terminal</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If <code>true</code>, specifies that the <code>output</code> should be 8341cb0ef41Sopenharmony_citreated as a TTY terminal. 8351cb0ef41Sopenharmony_ci<strong>Default:</strong> checking the value of the <code>isTTY</code> property on the <code>output</code> 8361cb0ef41Sopenharmony_cistream upon instantiation.</li> 8371cb0ef41Sopenharmony_ci<li><code>eval</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> The function to be used when evaluating each given line 8381cb0ef41Sopenharmony_ciof input. <strong>Default:</strong> an async wrapper for the JavaScript <code>eval()</code> 8391cb0ef41Sopenharmony_cifunction. An <code>eval</code> function can error with <code>repl.Recoverable</code> to indicate 8401cb0ef41Sopenharmony_cithe input was incomplete and prompt for additional lines.</li> 8411cb0ef41Sopenharmony_ci<li><code>useColors</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If <code>true</code>, specifies that the default <code>writer</code> 8421cb0ef41Sopenharmony_cifunction should include ANSI color styling to REPL output. If a custom 8431cb0ef41Sopenharmony_ci<code>writer</code> function is provided then this has no effect. <strong>Default:</strong> checking 8441cb0ef41Sopenharmony_cicolor support on the <code>output</code> stream if the REPL instance's <code>terminal</code> value 8451cb0ef41Sopenharmony_ciis <code>true</code>.</li> 8461cb0ef41Sopenharmony_ci<li><code>useGlobal</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If <code>true</code>, specifies that the default evaluation 8471cb0ef41Sopenharmony_cifunction will use the JavaScript <code>global</code> as the context as opposed to 8481cb0ef41Sopenharmony_cicreating a new separate context for the REPL instance. The node CLI REPL 8491cb0ef41Sopenharmony_cisets this value to <code>true</code>. <strong>Default:</strong> <code>false</code>.</li> 8501cb0ef41Sopenharmony_ci<li><code>ignoreUndefined</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> If <code>true</code>, specifies that the default writer 8511cb0ef41Sopenharmony_ciwill not output the return value of a command if it evaluates to 8521cb0ef41Sopenharmony_ci<code>undefined</code>. <strong>Default:</strong> <code>false</code>.</li> 8531cb0ef41Sopenharmony_ci<li><code>writer</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> The function to invoke to format the output of each 8541cb0ef41Sopenharmony_cicommand before writing to <code>output</code>. <strong>Default:</strong> <a href="util.html#utilinspectobject-options"><code>util.inspect()</code></a>.</li> 8551cb0ef41Sopenharmony_ci<li><code>completer</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type"><Function></a> An optional function used for custom Tab auto 8561cb0ef41Sopenharmony_cicompletion. See <a href="readline.html#use-of-the-completer-function"><code>readline.InterfaceCompleter</code></a> for an example.</li> 8571cb0ef41Sopenharmony_ci<li><code>replMode</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Symbol_type" class="type"><symbol></a> A flag that specifies whether the default evaluator 8581cb0ef41Sopenharmony_ciexecutes all JavaScript commands in strict mode or default (sloppy) mode. 8591cb0ef41Sopenharmony_ciAcceptable values are: 8601cb0ef41Sopenharmony_ci<ul> 8611cb0ef41Sopenharmony_ci<li><code>repl.REPL_MODE_SLOPPY</code> to evaluate expressions in sloppy mode.</li> 8621cb0ef41Sopenharmony_ci<li><code>repl.REPL_MODE_STRICT</code> to evaluate expressions in strict mode. This is 8631cb0ef41Sopenharmony_ciequivalent to prefacing every repl statement with <code>'use strict'</code>.</li> 8641cb0ef41Sopenharmony_ci</ul> 8651cb0ef41Sopenharmony_ci</li> 8661cb0ef41Sopenharmony_ci<li><code>breakEvalOnSigint</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> Stop evaluating the current piece of code when 8671cb0ef41Sopenharmony_ci<code>SIGINT</code> is received, such as when <kbd>Ctrl</kbd>+<kbd>C</kbd> is pressed. 8681cb0ef41Sopenharmony_ciThis cannot be used 8691cb0ef41Sopenharmony_citogether with a custom <code>eval</code> function. <strong>Default:</strong> <code>false</code>.</li> 8701cb0ef41Sopenharmony_ci<li><code>preview</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type"><boolean></a> Defines if the repl prints autocomplete and output 8711cb0ef41Sopenharmony_cipreviews or not. <strong>Default:</strong> <code>true</code> with the default eval function and 8721cb0ef41Sopenharmony_ci<code>false</code> in case a custom eval function is used. If <code>terminal</code> is falsy, then 8731cb0ef41Sopenharmony_cithere are no previews and the value of <code>preview</code> has no effect.</li> 8741cb0ef41Sopenharmony_ci</ul> 8751cb0ef41Sopenharmony_ci</li> 8761cb0ef41Sopenharmony_ci<li>Returns: <a href="repl.html#class-replserver" class="type"><repl.REPLServer></a></li> 8771cb0ef41Sopenharmony_ci</ul> 8781cb0ef41Sopenharmony_ci<p>The <code>repl.start()</code> method creates and starts a <a href="#class-replserver"><code>repl.REPLServer</code></a> instance.</p> 8791cb0ef41Sopenharmony_ci<p>If <code>options</code> is a string, then it specifies the input prompt:</p> 8801cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> repl = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:repl'</span>); 8811cb0ef41Sopenharmony_ci 8821cb0ef41Sopenharmony_ci<span class="hljs-comment">// a Unix style prompt</span> 8831cb0ef41Sopenharmony_cirepl.<span class="hljs-title function_">start</span>(<span class="hljs-string">'$ '</span>);</code> <button class="copy-button">copy</button></pre> 8841cb0ef41Sopenharmony_ci</section><section><h3>The Node.js REPL<span><a class="mark" href="#the-nodejs-repl" id="the-nodejs-repl">#</a></span><a aria-hidden="true" class="legacy" id="repl_the_node_js_repl"></a></h3> 8851cb0ef41Sopenharmony_ci<p>Node.js itself uses the <code>node:repl</code> module to provide its own interactive 8861cb0ef41Sopenharmony_ciinterface for executing JavaScript. This can be used by executing the Node.js 8871cb0ef41Sopenharmony_cibinary without passing any arguments (or by passing the <code>-i</code> argument):</p> 8881cb0ef41Sopenharmony_ci<pre><code class="language-console"><span class="hljs-meta prompt_">$ </span><span class="language-bash">node</span> 8891cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">const a = [1, 2, 3];</span> 8901cb0ef41Sopenharmony_ciundefined 8911cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">a</span> 8921cb0ef41Sopenharmony_ci[ 1, 2, 3 ] 8931cb0ef41Sopenharmony_ci<span class="hljs-meta prompt_">> </span><span class="language-bash">a.forEach((v) => {</span> 8941cb0ef41Sopenharmony_ci... console.log(v); 8951cb0ef41Sopenharmony_ci... }); 8961cb0ef41Sopenharmony_ci1 8971cb0ef41Sopenharmony_ci2 8981cb0ef41Sopenharmony_ci3</code> <button class="copy-button">copy</button></pre> 8991cb0ef41Sopenharmony_ci<h4>Environment variable options<span><a class="mark" href="#environment-variable-options" id="environment-variable-options">#</a></span><a aria-hidden="true" class="legacy" id="repl_environment_variable_options"></a></h4> 9001cb0ef41Sopenharmony_ci<p>Various behaviors of the Node.js REPL can be customized using the following 9011cb0ef41Sopenharmony_cienvironment variables:</p> 9021cb0ef41Sopenharmony_ci<ul> 9031cb0ef41Sopenharmony_ci<li><code>NODE_REPL_HISTORY</code>: When a valid path is given, persistent REPL history 9041cb0ef41Sopenharmony_ciwill be saved to the specified file rather than <code>.node_repl_history</code> in the 9051cb0ef41Sopenharmony_ciuser's home directory. Setting this value to <code>''</code> (an empty string) will 9061cb0ef41Sopenharmony_cidisable persistent REPL history. Whitespace will be trimmed from the value. 9071cb0ef41Sopenharmony_ciOn Windows platforms environment variables with empty values are invalid so 9081cb0ef41Sopenharmony_ciset this variable to one or more spaces to disable persistent REPL history.</li> 9091cb0ef41Sopenharmony_ci<li><code>NODE_REPL_HISTORY_SIZE</code>: Controls how many lines of history will be 9101cb0ef41Sopenharmony_cipersisted if history is available. Must be a positive number. 9111cb0ef41Sopenharmony_ci<strong>Default:</strong> <code>1000</code>.</li> 9121cb0ef41Sopenharmony_ci<li><code>NODE_REPL_MODE</code>: May be either <code>'sloppy'</code> or <code>'strict'</code>. <strong>Default:</strong> 9131cb0ef41Sopenharmony_ci<code>'sloppy'</code>, which will allow non-strict mode code to be run.</li> 9141cb0ef41Sopenharmony_ci</ul> 9151cb0ef41Sopenharmony_ci<h4>Persistent history<span><a class="mark" href="#persistent-history" id="persistent-history">#</a></span><a aria-hidden="true" class="legacy" id="repl_persistent_history"></a></h4> 9161cb0ef41Sopenharmony_ci<p>By default, the Node.js REPL will persist history between <code>node</code> REPL sessions 9171cb0ef41Sopenharmony_ciby saving inputs to a <code>.node_repl_history</code> file located in the user's home 9181cb0ef41Sopenharmony_cidirectory. This can be disabled by setting the environment variable 9191cb0ef41Sopenharmony_ci<code>NODE_REPL_HISTORY=''</code>.</p> 9201cb0ef41Sopenharmony_ci<h4>Using the Node.js REPL with advanced line-editors<span><a class="mark" href="#using-the-nodejs-repl-with-advanced-line-editors" id="using-the-nodejs-repl-with-advanced-line-editors">#</a></span><a aria-hidden="true" class="legacy" id="repl_using_the_node_js_repl_with_advanced_line_editors"></a></h4> 9211cb0ef41Sopenharmony_ci<p>For advanced line-editors, start Node.js with the environment variable 9221cb0ef41Sopenharmony_ci<code>NODE_NO_READLINE=1</code>. This will start the main and debugger REPL in canonical 9231cb0ef41Sopenharmony_citerminal settings, which will allow use with <code>rlwrap</code>.</p> 9241cb0ef41Sopenharmony_ci<p>For example, the following can be added to a <code>.bashrc</code> file:</p> 9251cb0ef41Sopenharmony_ci<pre><code class="language-text">alias node="env NODE_NO_READLINE=1 rlwrap node"</code> <button class="copy-button">copy</button></pre> 9261cb0ef41Sopenharmony_ci<h4>Starting multiple REPL instances against a single running instance<span><a class="mark" href="#starting-multiple-repl-instances-against-a-single-running-instance" id="starting-multiple-repl-instances-against-a-single-running-instance">#</a></span><a aria-hidden="true" class="legacy" id="repl_starting_multiple_repl_instances_against_a_single_running_instance"></a></h4> 9271cb0ef41Sopenharmony_ci<p>It is possible to create and run multiple REPL instances against a single 9281cb0ef41Sopenharmony_cirunning instance of Node.js that share a single <code>global</code> object but have 9291cb0ef41Sopenharmony_ciseparate I/O interfaces.</p> 9301cb0ef41Sopenharmony_ci<p>The following example, for instance, provides separate REPLs on <code>stdin</code>, a Unix 9311cb0ef41Sopenharmony_cisocket, and a TCP socket:</p> 9321cb0ef41Sopenharmony_ci<pre><code class="language-js"><span class="hljs-keyword">const</span> net = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:net'</span>); 9331cb0ef41Sopenharmony_ci<span class="hljs-keyword">const</span> repl = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:repl'</span>); 9341cb0ef41Sopenharmony_ci<span class="hljs-keyword">let</span> connections = <span class="hljs-number">0</span>; 9351cb0ef41Sopenharmony_ci 9361cb0ef41Sopenharmony_cirepl.<span class="hljs-title function_">start</span>({ 9371cb0ef41Sopenharmony_ci <span class="hljs-attr">prompt</span>: <span class="hljs-string">'Node.js via stdin> '</span>, 9381cb0ef41Sopenharmony_ci <span class="hljs-attr">input</span>: process.<span class="hljs-property">stdin</span>, 9391cb0ef41Sopenharmony_ci <span class="hljs-attr">output</span>: process.<span class="hljs-property">stdout</span>, 9401cb0ef41Sopenharmony_ci}); 9411cb0ef41Sopenharmony_ci 9421cb0ef41Sopenharmony_cinet.<span class="hljs-title function_">createServer</span>(<span class="hljs-function">(<span class="hljs-params">socket</span>) =></span> { 9431cb0ef41Sopenharmony_ci connections += <span class="hljs-number">1</span>; 9441cb0ef41Sopenharmony_ci repl.<span class="hljs-title function_">start</span>({ 9451cb0ef41Sopenharmony_ci <span class="hljs-attr">prompt</span>: <span class="hljs-string">'Node.js via Unix socket> '</span>, 9461cb0ef41Sopenharmony_ci <span class="hljs-attr">input</span>: socket, 9471cb0ef41Sopenharmony_ci <span class="hljs-attr">output</span>: socket, 9481cb0ef41Sopenharmony_ci }).<span class="hljs-title function_">on</span>(<span class="hljs-string">'exit'</span>, <span class="hljs-function">() =></span> { 9491cb0ef41Sopenharmony_ci socket.<span class="hljs-title function_">end</span>(); 9501cb0ef41Sopenharmony_ci }); 9511cb0ef41Sopenharmony_ci}).<span class="hljs-title function_">listen</span>(<span class="hljs-string">'/tmp/node-repl-sock'</span>); 9521cb0ef41Sopenharmony_ci 9531cb0ef41Sopenharmony_cinet.<span class="hljs-title function_">createServer</span>(<span class="hljs-function">(<span class="hljs-params">socket</span>) =></span> { 9541cb0ef41Sopenharmony_ci connections += <span class="hljs-number">1</span>; 9551cb0ef41Sopenharmony_ci repl.<span class="hljs-title function_">start</span>({ 9561cb0ef41Sopenharmony_ci <span class="hljs-attr">prompt</span>: <span class="hljs-string">'Node.js via TCP socket> '</span>, 9571cb0ef41Sopenharmony_ci <span class="hljs-attr">input</span>: socket, 9581cb0ef41Sopenharmony_ci <span class="hljs-attr">output</span>: socket, 9591cb0ef41Sopenharmony_ci }).<span class="hljs-title function_">on</span>(<span class="hljs-string">'exit'</span>, <span class="hljs-function">() =></span> { 9601cb0ef41Sopenharmony_ci socket.<span class="hljs-title function_">end</span>(); 9611cb0ef41Sopenharmony_ci }); 9621cb0ef41Sopenharmony_ci}).<span class="hljs-title function_">listen</span>(<span class="hljs-number">5001</span>);</code> <button class="copy-button">copy</button></pre> 9631cb0ef41Sopenharmony_ci<p>Running this application from the command line will start a REPL on stdin. 9641cb0ef41Sopenharmony_ciOther REPL clients may connect through the Unix socket or TCP socket. <code>telnet</code>, 9651cb0ef41Sopenharmony_cifor instance, is useful for connecting to TCP sockets, while <code>socat</code> can be used 9661cb0ef41Sopenharmony_cito connect to both Unix and TCP sockets.</p> 9671cb0ef41Sopenharmony_ci<p>By starting a REPL from a Unix socket-based server instead of stdin, it is 9681cb0ef41Sopenharmony_cipossible to connect to a long-running Node.js process without restarting it.</p> 9691cb0ef41Sopenharmony_ci<p>For an example of running a "full-featured" (<code>terminal</code>) REPL over 9701cb0ef41Sopenharmony_cia <code>net.Server</code> and <code>net.Socket</code> instance, see: 9711cb0ef41Sopenharmony_ci<a href="https://gist.github.com/TooTallNate/2209310">https://gist.github.com/TooTallNate/2209310</a>.</p> 9721cb0ef41Sopenharmony_ci<p>For an example of running a REPL instance over <a href="https://curl.haxx.se/docs/manpage.html"><code>curl(1)</code></a>, see: 9731cb0ef41Sopenharmony_ci<a href="https://gist.github.com/TooTallNate/2053342">https://gist.github.com/TooTallNate/2053342</a>.</p></section> 9741cb0ef41Sopenharmony_ci <!-- API END --> 9751cb0ef41Sopenharmony_ci </div> 9761cb0ef41Sopenharmony_ci </div> 9771cb0ef41Sopenharmony_ci </div> 9781cb0ef41Sopenharmony_ci</body> 9791cb0ef41Sopenharmony_ci</html> 980