/usr/share/doc/nodejs/html/api
<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <meta name="viewport" content="width=device-width"> <meta name="nodejs.org:node-version" content="v16.20.2"> <title>Internationalization support | Node.js v16.20.2 Documentation</title> <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Lato:400,700,400italic&display=fallback"> <link rel="stylesheet" href="assets/style.css"> <link rel="stylesheet" href="assets/hljs.css"> <link rel="canonical" href="https://nodejs.org/api/intl.html"> <script async defer src="assets/api.js" type="text/javascript"></script> </head> <body class="alt apidoc" id="api-section-intl"> <div id="content" class="clearfix"> <div id="column2" class="interior"> <div id="intro" class="interior"> <a href="/" title="Go back to the home page"> Node.js </a> </div> <ul> <li><a href="documentation.html" class="nav-documentation">About this documentation</a></li> <li><a href="synopsis.html" class="nav-synopsis">Usage and example</a></li> </ul> <hr class="line"> <ul> <li><a href="assert.html" class="nav-assert">Assertion testing</a></li> <li><a href="async_context.html" class="nav-async_context">Asynchronous context tracking</a></li> <li><a href="async_hooks.html" class="nav-async_hooks">Async hooks</a></li> <li><a href="buffer.html" class="nav-buffer">Buffer</a></li> <li><a href="addons.html" class="nav-addons">C++ addons</a></li> <li><a href="n-api.html" class="nav-n-api">C/C++ addons with Node-API</a></li> <li><a href="embedding.html" class="nav-embedding">C++ embedder API</a></li> <li><a href="child_process.html" class="nav-child_process">Child processes</a></li> <li><a href="cluster.html" class="nav-cluster">Cluster</a></li> <li><a href="cli.html" class="nav-cli">Command-line options</a></li> <li><a href="console.html" class="nav-console">Console</a></li> <li><a href="corepack.html" class="nav-corepack">Corepack</a></li> <li><a href="crypto.html" class="nav-crypto">Crypto</a></li> <li><a href="debugger.html" class="nav-debugger">Debugger</a></li> <li><a href="deprecations.html" class="nav-deprecations">Deprecated APIs</a></li> <li><a href="diagnostics_channel.html" class="nav-diagnostics_channel">Diagnostics Channel</a></li> <li><a href="dns.html" class="nav-dns">DNS</a></li> <li><a href="domain.html" class="nav-domain">Domain</a></li> <li><a href="errors.html" class="nav-errors">Errors</a></li> <li><a href="events.html" class="nav-events">Events</a></li> <li><a href="fs.html" class="nav-fs">File system</a></li> <li><a href="globals.html" class="nav-globals">Globals</a></li> <li><a href="http.html" class="nav-http">HTTP</a></li> <li><a href="http2.html" class="nav-http2">HTTP/2</a></li> <li><a href="https.html" class="nav-https">HTTPS</a></li> <li><a href="inspector.html" class="nav-inspector">Inspector</a></li> <li><a href="intl.html" class="nav-intl active">Internationalization</a></li> <li><a href="modules.html" class="nav-modules">Modules: CommonJS modules</a></li> <li><a href="esm.html" class="nav-esm">Modules: ECMAScript modules</a></li> <li><a href="module.html" class="nav-module">Modules: <code>node:module</code> API</a></li> <li><a href="packages.html" class="nav-packages">Modules: Packages</a></li> <li><a href="net.html" class="nav-net">Net</a></li> <li><a href="os.html" class="nav-os">OS</a></li> <li><a href="path.html" class="nav-path">Path</a></li> <li><a href="perf_hooks.html" class="nav-perf_hooks">Performance hooks</a></li> <li><a href="permissions.html" class="nav-permissions">Permissions</a></li> <li><a href="process.html" class="nav-process">Process</a></li> <li><a href="punycode.html" class="nav-punycode">Punycode</a></li> <li><a href="querystring.html" class="nav-querystring">Query strings</a></li> <li><a href="readline.html" class="nav-readline">Readline</a></li> <li><a href="repl.html" class="nav-repl">REPL</a></li> <li><a href="report.html" class="nav-report">Report</a></li> <li><a href="stream.html" class="nav-stream">Stream</a></li> <li><a href="string_decoder.html" class="nav-string_decoder">String decoder</a></li> <li><a href="test.html" class="nav-test">Test runner</a></li> <li><a href="timers.html" class="nav-timers">Timers</a></li> <li><a href="tls.html" class="nav-tls">TLS/SSL</a></li> <li><a href="tracing.html" class="nav-tracing">Trace events</a></li> <li><a href="tty.html" class="nav-tty">TTY</a></li> <li><a href="dgram.html" class="nav-dgram">UDP/datagram</a></li> <li><a href="url.html" class="nav-url">URL</a></li> <li><a href="util.html" class="nav-util">Utilities</a></li> <li><a href="v8.html" class="nav-v8">V8</a></li> <li><a href="vm.html" class="nav-vm">VM</a></li> <li><a href="wasi.html" class="nav-wasi">WASI</a></li> <li><a href="webcrypto.html" class="nav-webcrypto">Web Crypto API</a></li> <li><a href="webstreams.html" class="nav-webstreams">Web Streams API</a></li> <li><a href="worker_threads.html" class="nav-worker_threads">Worker threads</a></li> <li><a href="zlib.html" class="nav-zlib">Zlib</a></li> </ul> <hr class="line"> <ul> <li><a href="https://github.com/nodejs/node" class="nav-https-github-com-nodejs-node">Code repository and issue tracker</a></li> </ul> </div> <div id="column1" data-id="intl" class="interior"> <header class="header"> <div class="header-container"> <h1>Node.js v16.20.2 documentation</h1> <button class="theme-toggle-btn" id="theme-toggle-btn" title="Toggle dark mode/light mode" aria-label="Toggle dark mode/light mode" hidden> <svg xmlns="http://www.w3.org/2000/svg" class="icon dark-icon" height="24" width="24"> <path fill="none" d="M0 0h24v24H0z" /> <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"/> <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"/> </svg> <svg xmlns="http://www.w3.org/2000/svg" class="icon light-icon" height="24" width="24"> <path d="M0 0h24v24H0z" fill="none" /> <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"/> </svg> </button> </div> <div id="gtoc"> <ul> <li class="pinned-header">Node.js v16.20.2</li> <li class="picker-header"> <a href="#"> <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> Table of contents </a> <div class="picker"><div class="toc"><ul> <li><a href="#internationalization-support">Internationalization support</a> <ul> <li><a href="#options-for-building-nodejs">Options for building Node.js</a> <ul> <li><a href="#disable-all-internationalization-features-none">Disable all internationalization features (<code>none</code>)</a></li> <li><a href="#build-with-a-pre-installed-icu-system-icu">Build with a pre-installed ICU (<code>system-icu</code>)</a></li> <li><a href="#embed-a-limited-set-of-icu-data-small-icu">Embed a limited set of ICU data (<code>small-icu</code>)</a> <ul> <li><a href="#providing-icu-data-at-runtime">Providing ICU data at runtime</a></li> </ul> </li> <li><a href="#embed-the-entire-icu-full-icu">Embed the entire ICU (<code>full-icu</code>)</a></li> </ul> </li> <li><a href="#detecting-internationalization-support">Detecting internationalization support</a></li> </ul> </li> </ul></div></div> </li> <li class="picker-header"> <a href="#"> <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> Index </a> <div class="picker"><ul> <li><a href="documentation.html" class="nav-documentation">About this documentation</a></li> <li><a href="synopsis.html" class="nav-synopsis">Usage and example</a></li> <li> <a href="index.html">Index</a> </li> </ul> <hr class="line"> <ul> <li><a href="assert.html" class="nav-assert">Assertion testing</a></li> <li><a href="async_context.html" class="nav-async_context">Asynchronous context tracking</a></li> <li><a href="async_hooks.html" class="nav-async_hooks">Async hooks</a></li> <li><a href="buffer.html" class="nav-buffer">Buffer</a></li> <li><a href="addons.html" class="nav-addons">C++ addons</a></li> <li><a href="n-api.html" class="nav-n-api">C/C++ addons with Node-API</a></li> <li><a href="embedding.html" class="nav-embedding">C++ embedder API</a></li> <li><a href="child_process.html" class="nav-child_process">Child processes</a></li> <li><a href="cluster.html" class="nav-cluster">Cluster</a></li> <li><a href="cli.html" class="nav-cli">Command-line options</a></li> <li><a href="console.html" class="nav-console">Console</a></li> <li><a href="corepack.html" class="nav-corepack">Corepack</a></li> <li><a href="crypto.html" class="nav-crypto">Crypto</a></li> <li><a href="debugger.html" class="nav-debugger">Debugger</a></li> <li><a href="deprecations.html" class="nav-deprecations">Deprecated APIs</a></li> <li><a href="diagnostics_channel.html" class="nav-diagnostics_channel">Diagnostics Channel</a></li> <li><a href="dns.html" class="nav-dns">DNS</a></li> <li><a href="domain.html" class="nav-domain">Domain</a></li> <li><a href="errors.html" class="nav-errors">Errors</a></li> <li><a href="events.html" class="nav-events">Events</a></li> <li><a href="fs.html" class="nav-fs">File system</a></li> <li><a href="globals.html" class="nav-globals">Globals</a></li> <li><a href="http.html" class="nav-http">HTTP</a></li> <li><a href="http2.html" class="nav-http2">HTTP/2</a></li> <li><a href="https.html" class="nav-https">HTTPS</a></li> <li><a href="inspector.html" class="nav-inspector">Inspector</a></li> <li><a href="intl.html" class="nav-intl active">Internationalization</a></li> <li><a href="modules.html" class="nav-modules">Modules: CommonJS modules</a></li> <li><a href="esm.html" class="nav-esm">Modules: ECMAScript modules</a></li> <li><a href="module.html" class="nav-module">Modules: <code>node:module</code> API</a></li> <li><a href="packages.html" class="nav-packages">Modules: Packages</a></li> <li><a href="net.html" class="nav-net">Net</a></li> <li><a href="os.html" class="nav-os">OS</a></li> <li><a href="path.html" class="nav-path">Path</a></li> <li><a href="perf_hooks.html" class="nav-perf_hooks">Performance hooks</a></li> <li><a href="permissions.html" class="nav-permissions">Permissions</a></li> <li><a href="process.html" class="nav-process">Process</a></li> <li><a href="punycode.html" class="nav-punycode">Punycode</a></li> <li><a href="querystring.html" class="nav-querystring">Query strings</a></li> <li><a href="readline.html" class="nav-readline">Readline</a></li> <li><a href="repl.html" class="nav-repl">REPL</a></li> <li><a href="report.html" class="nav-report">Report</a></li> <li><a href="stream.html" class="nav-stream">Stream</a></li> <li><a href="string_decoder.html" class="nav-string_decoder">String decoder</a></li> <li><a href="test.html" class="nav-test">Test runner</a></li> <li><a href="timers.html" class="nav-timers">Timers</a></li> <li><a href="tls.html" class="nav-tls">TLS/SSL</a></li> <li><a href="tracing.html" class="nav-tracing">Trace events</a></li> <li><a href="tty.html" class="nav-tty">TTY</a></li> <li><a href="dgram.html" class="nav-dgram">UDP/datagram</a></li> <li><a href="url.html" class="nav-url">URL</a></li> <li><a href="util.html" class="nav-util">Utilities</a></li> <li><a href="v8.html" class="nav-v8">V8</a></li> <li><a href="vm.html" class="nav-vm">VM</a></li> <li><a href="wasi.html" class="nav-wasi">WASI</a></li> <li><a href="webcrypto.html" class="nav-webcrypto">Web Crypto API</a></li> <li><a href="webstreams.html" class="nav-webstreams">Web Streams API</a></li> <li><a href="worker_threads.html" class="nav-worker_threads">Worker threads</a></li> <li><a href="zlib.html" class="nav-zlib">Zlib</a></li> </ul> <hr class="line"> <ul> <li><a href="https://github.com/nodejs/node" class="nav-https-github-com-nodejs-node">Code repository and issue tracker</a></li> </ul></div> </li> <li class="picker-header"> <a href="#"> <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> Other versions </a> <div class="picker"><ol id="alt-docs"><li><a href="https://nodejs.org/docs/latest-v20.x/api/intl.html">20.x</a></li> <li><a href="https://nodejs.org/docs/latest-v19.x/api/intl.html">19.x</a></li> <li><a href="https://nodejs.org/docs/latest-v18.x/api/intl.html">18.x <b>LTS</b></a></li> <li><a href="https://nodejs.org/docs/latest-v17.x/api/intl.html">17.x</a></li> <li><a href="https://nodejs.org/docs/latest-v16.x/api/intl.html">16.x <b>LTS</b></a></li> <li><a href="https://nodejs.org/docs/latest-v15.x/api/intl.html">15.x</a></li> <li><a href="https://nodejs.org/docs/latest-v14.x/api/intl.html">14.x</a></li> <li><a href="https://nodejs.org/docs/latest-v13.x/api/intl.html">13.x</a></li> <li><a href="https://nodejs.org/docs/latest-v12.x/api/intl.html">12.x</a></li> <li><a href="https://nodejs.org/docs/latest-v11.x/api/intl.html">11.x</a></li> <li><a href="https://nodejs.org/docs/latest-v10.x/api/intl.html">10.x</a></li> <li><a href="https://nodejs.org/docs/latest-v9.x/api/intl.html">9.x</a></li> <li><a href="https://nodejs.org/docs/latest-v8.x/api/intl.html">8.x</a></li></ol></div> </li> <li class="picker-header"> <a href="#"> <span class="collapsed-arrow">►</span><span class="expanded-arrow">▼</span> Options </a> <div class="picker"> <ul> <li> <a href="all.html">View on single page</a> </li> <li> <a href="intl.json">View as JSON</a> </li> <li class="edit_on_github"><a href="https://github.com/nodejs/node/edit/main/doc/api/intl.md">Edit on GitHub</a></li> </ul> </div> </li> </ul> </div> <hr> </header> <details id="toc" open><summary>Table of contents</summary><ul> <li><a href="#internationalization-support">Internationalization support</a> <ul> <li><a href="#options-for-building-nodejs">Options for building Node.js</a> <ul> <li><a href="#disable-all-internationalization-features-none">Disable all internationalization features (<code>none</code>)</a></li> <li><a href="#build-with-a-pre-installed-icu-system-icu">Build with a pre-installed ICU (<code>system-icu</code>)</a></li> <li><a href="#embed-a-limited-set-of-icu-data-small-icu">Embed a limited set of ICU data (<code>small-icu</code>)</a> <ul> <li><a href="#providing-icu-data-at-runtime">Providing ICU data at runtime</a></li> </ul> </li> <li><a href="#embed-the-entire-icu-full-icu">Embed the entire ICU (<code>full-icu</code>)</a></li> </ul> </li> <li><a href="#detecting-internationalization-support">Detecting internationalization support</a></li> </ul> </li> </ul></details> <div id="apicontent"> <h2>Internationalization support<span><a class="mark" href="#internationalization-support" id="internationalization-support">#</a></span><a aria-hidden="true" class="legacy" id="intl_internationalization_support"></a></h2> <p>Node.js has many features that make it easier to write internationalized programs. Some of them are:</p> <ul> <li>Locale-sensitive or Unicode-aware functions in the <a href="https://tc39.github.io/ecma262/">ECMAScript Language Specification</a>: <ul> <li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/normalize"><code>String.prototype.normalize()</code></a></li> <li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toLowerCase"><code>String.prototype.toLowerCase()</code></a></li> <li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase"><code>String.prototype.toUpperCase()</code></a></li> </ul> </li> <li>All functionality described in the <a href="https://tc39.github.io/ecma402/">ECMAScript Internationalization API Specification</a> (aka ECMA-402): <ul> <li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl"><code>Intl</code></a> object</li> <li>Locale-sensitive methods like <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/localeCompare"><code>String.prototype.localeCompare()</code></a> and <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toLocaleString"><code>Date.prototype.toLocaleString()</code></a></li> </ul> </li> <li>The <a href="url.html#the-whatwg-url-api">WHATWG URL parser</a>'s <a href="https://en.wikipedia.org/wiki/Internationalized_domain_name">internationalized domain names</a> (IDNs) support</li> <li><a href="buffer.html#buffertranscodesource-fromenc-toenc"><code>require('node:buffer').transcode()</code></a></li> <li>More accurate <a href="repl.html#repl">REPL</a> line editing</li> <li><a href="util.html#class-utiltextdecoder"><code>require('node:util').TextDecoder</code></a></li> <li><a href="https://github.com/tc39/proposal-regexp-unicode-property-escapes"><code>RegExp</code> Unicode Property Escapes</a></li> </ul> <p>Node.js and the underlying V8 engine use <a href="http://site.icu-project.org/">International Components for Unicode (ICU)</a> to implement these features in native C/C++ code. The full ICU data set is provided by Node.js by default. However, due to the size of the ICU data file, several options are provided for customizing the ICU data set either when building or running Node.js.</p> <section><h3>Options for building Node.js<span><a class="mark" href="#options-for-building-nodejs" id="options-for-building-nodejs">#</a></span><a aria-hidden="true" class="legacy" id="intl_options_for_building_node_js"></a></h3> <p>To control how ICU is used in Node.js, four <code>configure</code> options are available during compilation. Additional details on how to compile Node.js are documented in <a href="https://github.com/nodejs/node/blob/HEAD/BUILDING.md">BUILDING.md</a>.</p> <ul> <li><code>--with-intl=none</code>/<code>--without-intl</code></li> <li><code>--with-intl=system-icu</code></li> <li><code>--with-intl=small-icu</code></li> <li><code>--with-intl=full-icu</code> (default)</li> </ul> <p>An overview of available Node.js and JavaScript features for each <code>configure</code> option:</p> <table><thead><tr><th>Feature</th><th><code>none</code></th><th><code>system-icu</code></th><th><code>small-icu</code></th><th><code>full-icu</code></th></tr></thead><tbody><tr><td><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/normalize"><code>String.prototype.normalize()</code></a></td><td>none (function is no-op)</td><td>full</td><td>full</td><td>full</td></tr><tr><td><code>String.prototype.to*Case()</code></td><td>full</td><td>full</td><td>full</td><td>full</td></tr><tr><td><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl"><code>Intl</code></a></td><td>none (object does not exist)</td><td>partial/full (depends on OS)</td><td>partial (English-only)</td><td>full</td></tr><tr><td><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/localeCompare"><code>String.prototype.localeCompare()</code></a></td><td>partial (not locale-aware)</td><td>full</td><td>full</td><td>full</td></tr><tr><td><code>String.prototype.toLocale*Case()</code></td><td>partial (not locale-aware)</td><td>full</td><td>full</td><td>full</td></tr><tr><td><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/toLocaleString"><code>Number.prototype.toLocaleString()</code></a></td><td>partial (not locale-aware)</td><td>partial/full (depends on OS)</td><td>partial (English-only)</td><td>full</td></tr><tr><td><code>Date.prototype.toLocale*String()</code></td><td>partial (not locale-aware)</td><td>partial/full (depends on OS)</td><td>partial (English-only)</td><td>full</td></tr><tr><td><a href="url.html#legacy-url-api">Legacy URL Parser</a></td><td>partial (no IDN support)</td><td>full</td><td>full</td><td>full</td></tr><tr><td><a href="url.html#the-whatwg-url-api">WHATWG URL Parser</a></td><td>partial (no IDN support)</td><td>full</td><td>full</td><td>full</td></tr><tr><td><a href="buffer.html#buffertranscodesource-fromenc-toenc"><code>require('node:buffer').transcode()</code></a></td><td>none (function does not exist)</td><td>full</td><td>full</td><td>full</td></tr><tr><td><a href="repl.html#repl">REPL</a></td><td>partial (inaccurate line editing)</td><td>full</td><td>full</td><td>full</td></tr><tr><td><a href="util.html#class-utiltextdecoder"><code>require('node:util').TextDecoder</code></a></td><td>partial (basic encodings support)</td><td>partial/full (depends on OS)</td><td>partial (Unicode-only)</td><td>full</td></tr><tr><td><a href="https://github.com/tc39/proposal-regexp-unicode-property-escapes"><code>RegExp</code> Unicode Property Escapes</a></td><td>none (invalid <code>RegExp</code> error)</td><td>full</td><td>full</td><td>full</td></tr></tbody></table> <p>The "(not locale-aware)" designation denotes that the function carries out its operation just like the non-<code>Locale</code> version of the function, if one exists. For example, under <code>none</code> mode, <code>Date.prototype.toLocaleString()</code>'s operation is identical to that of <code>Date.prototype.toString()</code>.</p> <h4>Disable all internationalization features (<code>none</code>)<span><a class="mark" href="#disable-all-internationalization-features-none" id="disable-all-internationalization-features-none">#</a></span><a aria-hidden="true" class="legacy" id="intl_disable_all_internationalization_features_none"></a></h4> <p>If this option is chosen, ICU is disabled and most internationalization features mentioned above will be <strong>unavailable</strong> in the resulting <code>node</code> binary.</p> <h4>Build with a pre-installed ICU (<code>system-icu</code>)<span><a class="mark" href="#build-with-a-pre-installed-icu-system-icu" id="build-with-a-pre-installed-icu-system-icu">#</a></span><a aria-hidden="true" class="legacy" id="intl_build_with_a_pre_installed_icu_system_icu"></a></h4> <p>Node.js can link against an ICU build already installed on the system. In fact, most Linux distributions already come with ICU installed, and this option would make it possible to reuse the same set of data used by other components in the OS.</p> <p>Functionalities that only require the ICU library itself, such as <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/normalize"><code>String.prototype.normalize()</code></a> and the <a href="url.html#the-whatwg-url-api">WHATWG URL parser</a>, are fully supported under <code>system-icu</code>. Features that require ICU locale data in addition, such as <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DateTimeFormat"><code>Intl.DateTimeFormat</code></a> <em>may</em> be fully or partially supported, depending on the completeness of the ICU data installed on the system.</p> <h4>Embed a limited set of ICU data (<code>small-icu</code>)<span><a class="mark" href="#embed-a-limited-set-of-icu-data-small-icu" id="embed-a-limited-set-of-icu-data-small-icu">#</a></span><a aria-hidden="true" class="legacy" id="intl_embed_a_limited_set_of_icu_data_small_icu"></a></h4> <p>This option makes the resulting binary link against the ICU library statically, and includes a subset of ICU data (typically only the English locale) within the <code>node</code> executable.</p> <p>Functionalities that only require the ICU library itself, such as <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/normalize"><code>String.prototype.normalize()</code></a> and the <a href="url.html#the-whatwg-url-api">WHATWG URL parser</a>, are fully supported under <code>small-icu</code>. Features that require ICU locale data in addition, such as <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DateTimeFormat"><code>Intl.DateTimeFormat</code></a>, generally only work with the English locale:</p> <pre><code class="language-js"><span class="hljs-keyword">const</span> january = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Date</span>(<span class="hljs-number">9e8</span>); <span class="hljs-keyword">const</span> english = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Intl</span>.<span class="hljs-title class_">DateTimeFormat</span>(<span class="hljs-string">'en'</span>, { <span class="hljs-attr">month</span>: <span class="hljs-string">'long'</span> }); <span class="hljs-keyword">const</span> spanish = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Intl</span>.<span class="hljs-title class_">DateTimeFormat</span>(<span class="hljs-string">'es'</span>, { <span class="hljs-attr">month</span>: <span class="hljs-string">'long'</span> }); <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(english.<span class="hljs-title function_">format</span>(january)); <span class="hljs-comment">// Prints "January"</span> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(spanish.<span class="hljs-title function_">format</span>(january)); <span class="hljs-comment">// Prints either "M01" or "January" on small-icu, depending on the user’s default locale</span> <span class="hljs-comment">// Should print "enero"</span></code></pre> <p>This mode provides a balance between features and binary size.</p> <h5>Providing ICU data at runtime<span><a class="mark" href="#providing-icu-data-at-runtime" id="providing-icu-data-at-runtime">#</a></span><a aria-hidden="true" class="legacy" id="intl_providing_icu_data_at_runtime"></a></h5> <p>If the <code>small-icu</code> option is used, one can still provide additional locale data at runtime so that the JS methods would work for all ICU locales. Assuming the data file is stored at <code>/some/directory</code>, it can be made available to ICU through either:</p> <ul> <li> <p>The <a href="cli.html#node_icu_datafile"><code>NODE_ICU_DATA</code></a> environment variable:</p> <pre><code class="language-bash"><span class="hljs-built_in">env</span> NODE_ICU_DATA=/some/directory node</code></pre> </li> <li> <p>The <a href="cli.html#--icu-data-dirfile"><code>--icu-data-dir</code></a> CLI parameter:</p> <pre><code class="language-bash">node --icu-data-dir=/some/directory</code></pre> </li> </ul> <p>(If both are specified, the <code>--icu-data-dir</code> CLI parameter takes precedence.)</p> <p>ICU is able to automatically find and load a variety of data formats, but the data must be appropriate for the ICU version, and the file correctly named. The most common name for the data file is <code>icudt6X[bl].dat</code>, where <code>6X</code> denotes the intended ICU version, and <code>b</code> or <code>l</code> indicates the system's endianness. Check <a href="http://userguide.icu-project.org/icudata">"ICU Data"</a> article in the ICU User Guide for other supported formats and more details on ICU data in general.</p> <p>The <a href="https://www.npmjs.com/package/full-icu">full-icu</a> npm module can greatly simplify ICU data installation by detecting the ICU version of the running <code>node</code> executable and downloading the appropriate data file. After installing the module through <code>npm i full-icu</code>, the data file will be available at <code>./node_modules/full-icu</code>. This path can be then passed either to <code>NODE_ICU_DATA</code> or <code>--icu-data-dir</code> as shown above to enable full <code>Intl</code> support.</p> <h4>Embed the entire ICU (<code>full-icu</code>)<span><a class="mark" href="#embed-the-entire-icu-full-icu" id="embed-the-entire-icu-full-icu">#</a></span><a aria-hidden="true" class="legacy" id="intl_embed_the_entire_icu_full_icu"></a></h4> <p>This option makes the resulting binary link against ICU statically and include a full set of ICU data. A binary created this way has no further external dependencies and supports all locales, but might be rather large. This is the default behavior if no <code>--with-intl</code> flag is passed. The official binaries are also built in this mode.</p> </section><section><h3>Detecting internationalization support<span><a class="mark" href="#detecting-internationalization-support" id="detecting-internationalization-support">#</a></span><a aria-hidden="true" class="legacy" id="intl_detecting_internationalization_support"></a></h3> <p>To verify that ICU is enabled at all (<code>system-icu</code>, <code>small-icu</code>, or <code>full-icu</code>), simply checking the existence of <code>Intl</code> should suffice:</p> <pre><code class="language-js"><span class="hljs-keyword">const</span> hasICU = <span class="hljs-keyword">typeof</span> <span class="hljs-title class_">Intl</span> === <span class="hljs-string">'object'</span>;</code></pre> <p>Alternatively, checking for <code>process.versions.icu</code>, a property defined only when ICU is enabled, works too:</p> <pre><code class="language-js"><span class="hljs-keyword">const</span> hasICU = <span class="hljs-keyword">typeof</span> process.<span class="hljs-property">versions</span>.<span class="hljs-property">icu</span> === <span class="hljs-string">'string'</span>;</code></pre> <p>To check for support for a non-English locale (i.e. <code>full-icu</code> or <code>system-icu</code>), <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DateTimeFormat"><code>Intl.DateTimeFormat</code></a> can be a good distinguishing factor:</p> <pre><code class="language-js"><span class="hljs-keyword">const</span> hasFullICU = (<span class="hljs-function">() =></span> { <span class="hljs-keyword">try</span> { <span class="hljs-keyword">const</span> january = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Date</span>(<span class="hljs-number">9e8</span>); <span class="hljs-keyword">const</span> spanish = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Intl</span>.<span class="hljs-title class_">DateTimeFormat</span>(<span class="hljs-string">'es'</span>, { <span class="hljs-attr">month</span>: <span class="hljs-string">'long'</span> }); <span class="hljs-keyword">return</span> spanish.<span class="hljs-title function_">format</span>(january) === <span class="hljs-string">'enero'</span>; } <span class="hljs-keyword">catch</span> (err) { <span class="hljs-keyword">return</span> <span class="hljs-literal">false</span>; } })();</code></pre> <p>For more verbose tests for <code>Intl</code> support, the following resources may be found to be helpful:</p> <ul> <li><a href="https://github.com/srl295/btest402">btest402</a>: Generally used to check whether Node.js with <code>Intl</code> support is built correctly.</li> <li><a href="https://github.com/tc39/test262/tree/HEAD/test/intl402">Test262</a>: ECMAScript's official conformance test suite includes a section dedicated to ECMA-402.</li> </ul></section> <!-- API END --> </div> </div> </div> </body> </html>
.
Edit
..
Edit
addons.html
Edit
addons.json
Edit
addons.md
Edit
all.html
Edit
all.json
Edit
assert.html
Edit
assert.json
Edit
assert.md
Edit
assets
Edit
async_context.html
Edit
async_context.json
Edit
async_context.md
Edit
async_hooks.html
Edit
async_hooks.json
Edit
async_hooks.md
Edit
buffer.html
Edit
buffer.json
Edit
buffer.md
Edit
child_process.html
Edit
child_process.json
Edit
child_process.md
Edit
cli.html
Edit
cli.json
Edit
cli.md
Edit
cluster.html
Edit
cluster.json
Edit
cluster.md
Edit
console.html
Edit
console.json
Edit
console.md
Edit
corepack.html
Edit
corepack.json
Edit
corepack.md
Edit
crypto.html
Edit
crypto.json
Edit
crypto.md
Edit
debugger.html
Edit
debugger.json
Edit
debugger.md
Edit
deprecations.html
Edit
deprecations.json
Edit
deprecations.md
Edit
dgram.html
Edit
dgram.json
Edit
dgram.md
Edit
diagnostics_channel.html
Edit
diagnostics_channel.json
Edit
diagnostics_channel.md
Edit
dns.html
Edit
dns.json
Edit
dns.md
Edit
documentation.html
Edit
documentation.json
Edit
documentation.md
Edit
domain.html
Edit
domain.json
Edit
domain.md
Edit
embedding.html
Edit
embedding.json
Edit
embedding.md
Edit
errors.html
Edit
errors.json
Edit
errors.md
Edit
esm.html
Edit
esm.json
Edit
esm.md
Edit
events.html
Edit
events.json
Edit
events.md
Edit
fs.html
Edit
fs.json
Edit
fs.md
Edit
globals.html
Edit
globals.json
Edit
globals.md
Edit
http.html
Edit
http.json
Edit
http.md
Edit
http2.html
Edit
http2.json
Edit
http2.md
Edit
https.html
Edit
https.json
Edit
https.md
Edit
index.html
Edit
index.json
Edit
index.md
Edit
inspector.html
Edit
inspector.json
Edit
inspector.md
Edit
intl.html
Edit
intl.json
Edit
intl.md
Edit
module.html
Edit
module.json
Edit
module.md
Edit
modules.html
Edit
modules.json
Edit
modules.md
Edit
n-api.html
Edit
n-api.json
Edit
n-api.md
Edit
net.html
Edit
net.json
Edit
net.md
Edit
os.html
Edit
os.json
Edit
os.md
Edit
packages.html
Edit
packages.json
Edit
packages.md
Edit
path.html
Edit
path.json
Edit
path.md
Edit
perf_hooks.html
Edit
perf_hooks.json
Edit
perf_hooks.md
Edit
permissions.html
Edit
permissions.json
Edit
permissions.md
Edit
policy.html
Edit
policy.json
Edit
policy.md
Edit
process.html
Edit
process.json
Edit
process.md
Edit
punycode.html
Edit
punycode.json
Edit
punycode.md
Edit
querystring.html
Edit
querystring.json
Edit
querystring.md
Edit
readline.html
Edit
readline.json
Edit
readline.md
Edit
repl.html
Edit
repl.json
Edit
repl.md
Edit
report.html
Edit
report.json
Edit
report.md
Edit
stream.html
Edit
stream.json
Edit
stream.md
Edit
string_decoder.html
Edit
string_decoder.json
Edit
string_decoder.md
Edit
synopsis.html
Edit
synopsis.json
Edit
synopsis.md
Edit
test.html
Edit
test.json
Edit
test.md
Edit
timers.html
Edit
timers.json
Edit
timers.md
Edit
tls.html
Edit
tls.json
Edit
tls.md
Edit
tracing.html
Edit
tracing.json
Edit
tracing.md
Edit
tty.html
Edit
tty.json
Edit
tty.md
Edit
url.html
Edit
url.json
Edit
url.md
Edit
util.html
Edit
util.json
Edit
util.md
Edit
v8.html
Edit
v8.json
Edit
v8.md
Edit
vm.html
Edit
vm.json
Edit
vm.md
Edit
wasi.html
Edit
wasi.json
Edit
wasi.md
Edit
webcrypto.html
Edit
webcrypto.json
Edit
webcrypto.md
Edit
webstreams.html
Edit
webstreams.json
Edit
webstreams.md
Edit
worker_threads.html
Edit
worker_threads.json
Edit
worker_threads.md
Edit
zlib.html
Edit
zlib.json
Edit
zlib.md
Edit