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      <details id="toc" open><summary>Table of contents</summary><ul>
<li><a href="#globals_global_objects">Global objects</a>
<ul>
<li><span class="stability_1"><a href="#globals_class_abortcontroller">Class: <code>AbortController</code></a></span>
<ul>
<li><a href="#globals_abortcontroller_abort"><code>abortController.abort()</code></a></li>
<li><a href="#globals_abortcontroller_signal"><code>abortController.signal</code></a></li>
<li><a href="#globals_class_abortsignal">Class: <code>AbortSignal</code></a>
<ul>
<li><a href="#globals_static_method_abortsignal_abort">Static method: <code>AbortSignal.abort()</code></a></li>
<li><a href="#globals_event_abort">Event: <code>'abort'</code></a></li>
<li><a href="#globals_abortsignal_aborted"><code>abortSignal.aborted</code></a></li>
<li><a href="#globals_abortsignal_onabort"><code>abortSignal.onabort</code></a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#globals_class_buffer">Class: <code>Buffer</code></a></li>
<li><a href="#globals_dirname"><code>__dirname</code></a></li>
<li><a href="#globals_filename"><code>__filename</code></a></li>
<li><a href="#globals_clearimmediate_immediateobject"><code>clearImmediate(immediateObject)</code></a></li>
<li><a href="#globals_clearinterval_intervalobject"><code>clearInterval(intervalObject)</code></a></li>
<li><a href="#globals_cleartimeout_timeoutobject"><code>clearTimeout(timeoutObject)</code></a></li>
<li><a href="#globals_console"><code>console</code></a></li>
<li><a href="#globals_exports"><code>exports</code></a></li>
<li><a href="#globals_global"><code>global</code></a></li>
<li><a href="#globals_module"><code>module</code></a></li>
<li><a href="#globals_process"><code>process</code></a></li>
<li><a href="#globals_queuemicrotask_callback"><code>queueMicrotask(callback)</code></a></li>
<li><a href="#globals_require"><code>require()</code></a></li>
<li><a href="#globals_setimmediate_callback_args"><code>setImmediate(callback[, ...args])</code></a></li>
<li><a href="#globals_setinterval_callback_delay_args"><code>setInterval(callback, delay[, ...args])</code></a></li>
<li><a href="#globals_settimeout_callback_delay_args"><code>setTimeout(callback, delay[, ...args])</code></a></li>
<li><a href="#globals_textdecoder"><code>TextDecoder</code></a></li>
<li><a href="#globals_textencoder"><code>TextEncoder</code></a></li>
<li><a href="#globals_url"><code>URL</code></a></li>
<li><a href="#globals_urlsearchparams"><code>URLSearchParams</code></a></li>
<li><a href="#globals_webassembly"><code>WebAssembly</code></a></li>
</ul>
</li>
</ul></details>

      <div id="apicontent">
        <h2>Global objects<span><a class="mark" href="#globals_global_objects" id="globals_global_objects">#</a></span></h2>


<p>These objects are available in all modules. The following variables may appear
to be global but are not. They exist only in the scope of modules, see the
<a href="modules.html">module system documentation</a>:</p>
<ul>
<li><a href="modules.html#modules_dirname"><code>__dirname</code></a></li>
<li><a href="modules.html#modules_filename"><code>__filename</code></a></li>
<li><a href="modules.html#modules_exports"><code>exports</code></a></li>
<li><a href="modules.html#modules_module"><code>module</code></a></li>
<li><a href="modules.html#modules_require_id"><code>require()</code></a></li>
</ul>
<p>The objects listed here are specific to Node.js. There are <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects">built-in objects</a>
that are part of the JavaScript language itself, which are also globally
accessible.</p>
<section><h3>Class: <code>AbortController</code><span><a class="mark" href="#globals_class_abortcontroller" id="globals_class_abortcontroller">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v14.17.0</span>
</div>
<p></p><div class="api_stability api_stability_1"><a href="documentation.html#documentation_stability_index">Stability: 1</a> - Experimental</div><p></p>

<p>A utility class used to signal cancelation in selected <code>Promise</code>-based APIs.
The API is based on the Web API <a href="https://developer.mozilla.org/en-US/docs/Web/API/AbortController"><code>AbortController</code></a>.</p>
<p>To use, launch Node.js using the <code>--experimental-abortcontroller</code> flag.</p>
<pre><code class="language-js"><span class="hljs-keyword">const</span> ac = <span class="hljs-keyword">new</span> <span class="hljs-title class_">AbortController</span>();

ac.<span class="hljs-property">signal</span>.<span class="hljs-title function_">addEventListener</span>(<span class="hljs-string">'abort'</span>, <span class="hljs-function">() =></span> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'Aborted!'</span>),
                           { <span class="hljs-attr">once</span>: <span class="hljs-literal">true</span> });

ac.<span class="hljs-title function_">abort</span>();

<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(ac.<span class="hljs-property">signal</span>.<span class="hljs-property">aborted</span>);  <span class="hljs-comment">// Prints True</span></code></pre>
<h4><code>abortController.abort()</code><span><a class="mark" href="#globals_abortcontroller_abort" id="globals_abortcontroller_abort">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v14.17.0</span>
</div>
<p>Triggers the abort signal, causing the <code>abortController.signal</code> to emit
the <code>'abort'</code> event.</p>
<h4><code>abortController.signal</code><span><a class="mark" href="#globals_abortcontroller_signal" id="globals_abortcontroller_signal">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v14.17.0</span>
</div>
<ul>
<li>Type: <a href="globals.html#globals_class_abortsignal" class="type">&#x3C;AbortSignal></a></li>
</ul>
<h4>Class: <code>AbortSignal</code><span><a class="mark" href="#globals_class_abortsignal" id="globals_class_abortsignal">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v14.17.0</span>
</div>
<ul>
<li>Extends: <a href="events.html#events_class_eventtarget" class="type">&#x3C;EventTarget></a></li>
</ul>
<p>The <code>AbortSignal</code> is used to notify observers when the
<code>abortController.abort()</code> method is called.</p>
<h5>Static method: <code>AbortSignal.abort()</code><span><a class="mark" href="#globals_static_method_abortsignal_abort" id="globals_static_method_abortsignal_abort">#</a></span></h5>
<div class="api_metadata">
<span>Added in: v14.17.0</span>
</div>
<ul>
<li>Returns: <a href="globals.html#globals_class_abortsignal" class="type">&#x3C;AbortSignal></a></li>
</ul>
<p>Returns a new already aborted <code>AbortSignal</code>.</p>
<h5>Event: <code>'abort'</code><span><a class="mark" href="#globals_event_abort" id="globals_event_abort">#</a></span></h5>
<div class="api_metadata">
<span>Added in: v14.17.0</span>
</div>
<p>The <code>'abort'</code> event is emitted when the <code>abortController.abort()</code> method
is called. The callback is invoked with a single object argument with a
single <code>type</code> property set to <code>'abort'</code>:</p>
<pre><code class="language-js"><span class="hljs-keyword">const</span> ac = <span class="hljs-keyword">new</span> <span class="hljs-title class_">AbortController</span>();

<span class="hljs-comment">// Use either the onabort property...</span>
ac.<span class="hljs-property">signal</span>.<span class="hljs-property">onabort</span> = <span class="hljs-function">() =></span> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'aborted!'</span>);

<span class="hljs-comment">// Or the EventTarget API...</span>
ac.<span class="hljs-property">signal</span>.<span class="hljs-title function_">addEventListener</span>(<span class="hljs-string">'abort'</span>, <span class="hljs-function">(<span class="hljs-params">event</span>) =></span> {
  <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(event.<span class="hljs-property">type</span>);  <span class="hljs-comment">// Prints 'abort'</span>
}, { <span class="hljs-attr">once</span>: <span class="hljs-literal">true</span> });

ac.<span class="hljs-title function_">abort</span>();</code></pre>
<p>The <code>AbortController</code> with which the <code>AbortSignal</code> is associated will only
ever trigger the <code>'abort'</code> event once. We recommended that code check
that the <code>abortSignal.aborted</code> attribute is <code>false</code> before adding an <code>'abort'</code>
event listener.</p>
<p>Any event listeners attached to the <code>AbortSignal</code> should use the
<code>{ once: true }</code> option (or, if using the <code>EventEmitter</code> APIs to attach a
listener, use the <code>once()</code> method) to ensure that the event listener is
removed as soon as the <code>'abort'</code> event is handled. Failure to do so may
result in memory leaks.</p>
<h5><code>abortSignal.aborted</code><span><a class="mark" href="#globals_abortsignal_aborted" id="globals_abortsignal_aborted">#</a></span></h5>
<div class="api_metadata">
<span>Added in: v14.17.0</span>
</div>
<ul>
<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type">&#x3C;boolean></a> True after the <code>AbortController</code> has been aborted.</li>
</ul>
<h5><code>abortSignal.onabort</code><span><a class="mark" href="#globals_abortsignal_onabort" id="globals_abortsignal_onabort">#</a></span></h5>
<div class="api_metadata">
<span>Added in: v14.17.0</span>
</div>
<ul>
<li>Type: <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type">&#x3C;Function></a></li>
</ul>
<p>An optional callback function that may be set by user code to be notified
when the <code>abortController.abort()</code> function has been called.</p>
</section><section><h3>Class: <code>Buffer</code><span><a class="mark" href="#globals_class_buffer" id="globals_class_buffer">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.1.103</span>
</div>

<ul>
<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type">&#x3C;Function></a></li>
</ul>
<p>Used to handle binary data. See the <a href="buffer.html">buffer section</a>.</p>
</section><section><h3><code>__dirname</code><span><a class="mark" href="#globals_dirname" id="globals_dirname">#</a></span></h3>
<p>This variable may appear to be global but is not. See <a href="modules.html#modules_dirname"><code>__dirname</code></a>.</p>
</section><section><h3><code>__filename</code><span><a class="mark" href="#globals_filename" id="globals_filename">#</a></span></h3>
<p>This variable may appear to be global but is not. See <a href="modules.html#modules_filename"><code>__filename</code></a>.</p>
</section><section><h3><code>clearImmediate(immediateObject)</code><span><a class="mark" href="#globals_clearimmediate_immediateobject" id="globals_clearimmediate_immediateobject">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.9.1</span>
</div>

<p><a href="timers.html#timers_clearimmediate_immediate"><code>clearImmediate</code></a> is described in the <a href="timers.html">timers</a> section.</p>
</section><section><h3><code>clearInterval(intervalObject)</code><span><a class="mark" href="#globals_clearinterval_intervalobject" id="globals_clearinterval_intervalobject">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.0.1</span>
</div>

<p><a href="timers.html#timers_clearinterval_timeout"><code>clearInterval</code></a> is described in the <a href="timers.html">timers</a> section.</p>
</section><section><h3><code>clearTimeout(timeoutObject)</code><span><a class="mark" href="#globals_cleartimeout_timeoutobject" id="globals_cleartimeout_timeoutobject">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.0.1</span>
</div>

<p><a href="timers.html#timers_cleartimeout_timeout"><code>clearTimeout</code></a> is described in the <a href="timers.html">timers</a> section.</p>
</section><section><h3><code>console</code><span><a class="mark" href="#globals_console" id="globals_console">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.1.100</span>
</div>

<ul>
<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type">&#x3C;Object></a></li>
</ul>
<p>Used to print to stdout and stderr. See the <a href="console.html"><code>console</code></a> section.</p>
</section><section><h3><code>exports</code><span><a class="mark" href="#globals_exports" id="globals_exports">#</a></span></h3>
<p>This variable may appear to be global but is not. See <a href="modules.html#modules_exports"><code>exports</code></a>.</p>
</section><section><h3><code>global</code><span><a class="mark" href="#globals_global" id="globals_global">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.1.27</span>
</div>

<ul>
<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type">&#x3C;Object></a> The global namespace object.</li>
</ul>
<p>In browsers, the top-level scope is the global scope. This means that
within the browser <code>var something</code> will define a new global variable. In
Node.js this is different. The top-level scope is not the global scope;
<code>var something</code> inside a Node.js module will be local to that module.</p>
</section><section><h3><code>module</code><span><a class="mark" href="#globals_module" id="globals_module">#</a></span></h3>
<p>This variable may appear to be global but is not. See <a href="modules.html#modules_module"><code>module</code></a>.</p>
</section><section><h3><code>process</code><span><a class="mark" href="#globals_process" id="globals_process">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.1.7</span>
</div>

<ul>
<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type">&#x3C;Object></a></li>
</ul>
<p>The process object. See the <a href="process.html#process_process"><code>process</code> object</a> section.</p>
</section><section><h3><code>queueMicrotask(callback)</code><span><a class="mark" href="#globals_queuemicrotask_callback" id="globals_queuemicrotask_callback">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v11.0.0</span>
</div>

<ul>
<li><code>callback</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function" class="type">&#x3C;Function></a> Function to be queued.</li>
</ul>
<p>The <code>queueMicrotask()</code> method queues a microtask to invoke <code>callback</code>. If
<code>callback</code> throws an exception, the <a href="process.html#process_process"><code>process</code> object</a> <code>'uncaughtException'</code>
event will be emitted.</p>
<p>The microtask queue is managed by V8 and may be used in a similar manner to
the <a href="process.html#process_process_nexttick_callback_args"><code>process.nextTick()</code></a> queue, which is managed by Node.js. The
<code>process.nextTick()</code> queue is always processed before the microtask queue
within each turn of the Node.js event loop.</p>
<pre><code class="language-js"><span class="hljs-comment">// Here, `queueMicrotask()` is used to ensure the 'load' event is always</span>
<span class="hljs-comment">// emitted asynchronously, and therefore consistently. Using</span>
<span class="hljs-comment">// `process.nextTick()` here would result in the 'load' event always emitting</span>
<span class="hljs-comment">// before any other promise jobs.</span>

<span class="hljs-title class_">DataHandler</span>.<span class="hljs-property"><span class="hljs-keyword">prototype</span></span>.<span class="hljs-property">load</span> = <span class="hljs-keyword">async</span> <span class="hljs-keyword">function</span> <span class="hljs-title function_">load</span>(<span class="hljs-params">key</span>) {
  <span class="hljs-keyword">const</span> hit = <span class="hljs-variable language_">this</span>.<span class="hljs-property">_cache</span>.<span class="hljs-title function_">get</span>(key);
  <span class="hljs-keyword">if</span> (hit !== <span class="hljs-literal">undefined</span>) {
    <span class="hljs-title function_">queueMicrotask</span>(<span class="hljs-function">() =></span> {
      <span class="hljs-variable language_">this</span>.<span class="hljs-title function_">emit</span>(<span class="hljs-string">'load'</span>, hit);
    });
    <span class="hljs-keyword">return</span>;
  }

  <span class="hljs-keyword">const</span> data = <span class="hljs-keyword">await</span> <span class="hljs-title function_">fetchData</span>(key);
  <span class="hljs-variable language_">this</span>.<span class="hljs-property">_cache</span>.<span class="hljs-title function_">set</span>(key, data);
  <span class="hljs-variable language_">this</span>.<span class="hljs-title function_">emit</span>(<span class="hljs-string">'load'</span>, data);
};</code></pre>
</section><section><h3><code>require()</code><span><a class="mark" href="#globals_require" id="globals_require">#</a></span></h3>
<p>This variable may appear to be global but is not. See <a href="modules.html#modules_require_id"><code>require()</code></a>.</p>
</section><section><h3><code>setImmediate(callback[, ...args])</code><span><a class="mark" href="#globals_setimmediate_callback_args" id="globals_setimmediate_callback_args">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.9.1</span>
</div>

<p><a href="timers.html#timers_setimmediate_callback_args"><code>setImmediate</code></a> is described in the <a href="timers.html">timers</a> section.</p>
</section><section><h3><code>setInterval(callback, delay[, ...args])</code><span><a class="mark" href="#globals_setinterval_callback_delay_args" id="globals_setinterval_callback_delay_args">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.0.1</span>
</div>

<p><a href="timers.html#timers_setinterval_callback_delay_args"><code>setInterval</code></a> is described in the <a href="timers.html">timers</a> section.</p>
</section><section><h3><code>setTimeout(callback, delay[, ...args])</code><span><a class="mark" href="#globals_settimeout_callback_delay_args" id="globals_settimeout_callback_delay_args">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v0.0.1</span>
</div>

<p><a href="timers.html#timers_settimeout_callback_delay_args"><code>setTimeout</code></a> is described in the <a href="timers.html">timers</a> section.</p>
</section><section><h3><code>TextDecoder</code><span><a class="mark" href="#globals_textdecoder" id="globals_textdecoder">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v11.0.0</span>
</div>

<p>The WHATWG <code>TextDecoder</code> class. See the <a href="util.html#util_class_util_textdecoder"><code>TextDecoder</code></a> section.</p>
</section><section><h3><code>TextEncoder</code><span><a class="mark" href="#globals_textencoder" id="globals_textencoder">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v11.0.0</span>
</div>

<p>The WHATWG <code>TextEncoder</code> class. See the <a href="util.html#util_class_util_textencoder"><code>TextEncoder</code></a> section.</p>
</section><section><h3><code>URL</code><span><a class="mark" href="#globals_url" id="globals_url">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v10.0.0</span>
</div>

<p>The WHATWG <code>URL</code> class. See the <a href="url.html#url_class_url"><code>URL</code></a> section.</p>
</section><section><h3><code>URLSearchParams</code><span><a class="mark" href="#globals_urlsearchparams" id="globals_urlsearchparams">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v10.0.0</span>
</div>

<p>The WHATWG <code>URLSearchParams</code> class. See the <a href="url.html#url_class_urlsearchparams"><code>URLSearchParams</code></a> section.</p>
</section><section><h3><code>WebAssembly</code><span><a class="mark" href="#globals_webassembly" id="globals_webassembly">#</a></span></h3>
<div class="api_metadata">
<span>Added in: v8.0.0</span>
</div>

<ul>
<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type">&#x3C;Object></a></li>
</ul>
<p>The object that acts as the namespace for all W3C
<a href="https://webassembly.org">WebAssembly</a> related functionality. See the
<a href="https://developer.mozilla.org/en-US/docs/WebAssembly">Mozilla Developer Network</a> for usage and compatibility.</p></section>
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