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      <details id="toc" open><summary>Table of contents</summary><ul>
<li><span class="stability_2"><a href="#console_console">Console</a></span>
<ul>
<li><a href="#console_class_console">Class: <code>Console</code></a>
<ul>
<li><a href="#console_new_console_stdout_stderr_ignoreerrors"><code>new Console(stdout[, stderr][, ignoreErrors])</code></a></li>
<li><a href="#console_new_console_options"><code>new Console(options)</code></a></li>
<li><a href="#console_console_assert_value_message"><code>console.assert(value[, ...message])</code></a></li>
<li><a href="#console_console_clear"><code>console.clear()</code></a></li>
<li><a href="#console_console_count_label"><code>console.count([label])</code></a></li>
<li><a href="#console_console_countreset_label"><code>console.countReset([label])</code></a></li>
<li><a href="#console_console_debug_data_args"><code>console.debug(data[, ...args])</code></a></li>
<li><a href="#console_console_dir_obj_options"><code>console.dir(obj[, options])</code></a></li>
<li><a href="#console_console_dirxml_data"><code>console.dirxml(...data)</code></a></li>
<li><a href="#console_console_error_data_args"><code>console.error([data][, ...args])</code></a></li>
<li><a href="#console_console_group_label"><code>console.group([...label])</code></a></li>
<li><a href="#console_console_groupcollapsed"><code>console.groupCollapsed()</code></a></li>
<li><a href="#console_console_groupend"><code>console.groupEnd()</code></a></li>
<li><a href="#console_console_info_data_args"><code>console.info([data][, ...args])</code></a></li>
<li><a href="#console_console_log_data_args"><code>console.log([data][, ...args])</code></a></li>
<li><a href="#console_console_table_tabulardata_properties"><code>console.table(tabularData[, properties])</code></a></li>
<li><a href="#console_console_time_label"><code>console.time([label])</code></a></li>
<li><a href="#console_console_timeend_label"><code>console.timeEnd([label])</code></a></li>
<li><a href="#console_console_timelog_label_data"><code>console.timeLog([label][, ...data])</code></a></li>
<li><a href="#console_console_trace_message_args"><code>console.trace([message][, ...args])</code></a></li>
<li><a href="#console_console_warn_data_args"><code>console.warn([data][, ...args])</code></a></li>
</ul>
</li>
<li><a href="#console_inspector_only_methods">Inspector only methods</a>
<ul>
<li><a href="#console_console_profile_label"><code>console.profile([label])</code></a></li>
<li><a href="#console_console_profileend_label"><code>console.profileEnd([label])</code></a></li>
<li><a href="#console_console_timestamp_label"><code>console.timeStamp([label])</code></a></li>
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      <div id="apicontent">
        <h2>Console<span><a class="mark" href="#console_console" id="console_console">#</a></span></h2>

<p></p><div class="api_stability api_stability_2"><a href="documentation.html#documentation_stability_index">Stability: 2</a> - Stable</div><p></p>
<p><strong>Source Code:</strong> <a href="https://github.com/nodejs/node/blob/v14.20.1/lib/console.js">lib/console.js</a></p>
<p>The <code>console</code> module provides a simple debugging console that is similar to the
JavaScript console mechanism provided by web browsers.</p>
<p>The module exports two specific components:</p>
<ul>
<li>A <code>Console</code> class with methods such as <code>console.log()</code>, <code>console.error()</code> and
<code>console.warn()</code> that can be used to write to any Node.js stream.</li>
<li>A global <code>console</code> instance configured to write to <a href="process.html#process_process_stdout"><code>process.stdout</code></a> and
<a href="process.html#process_process_stderr"><code>process.stderr</code></a>. The global <code>console</code> can be used without calling
<code>require('console')</code>.</li>
</ul>
<p><em><strong>Warning</strong></em>: The global console object's methods are neither consistently
synchronous like the browser APIs they resemble, nor are they consistently
asynchronous like all other Node.js streams. See the <a href="process.html#process_a_note_on_process_i_o">note on process I/O</a> for
more information.</p>
<p>Example using the global <code>console</code>:</p>
<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'hello world'</span>);
<span class="hljs-comment">// Prints: hello world, to stdout</span>
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'hello %s'</span>, <span class="hljs-string">'world'</span>);
<span class="hljs-comment">// Prints: hello world, to stdout</span>
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-keyword">new</span> <span class="hljs-title class_">Error</span>(<span class="hljs-string">'Whoops, something bad happened'</span>));
<span class="hljs-comment">// Prints error message and stack trace to stderr:</span>
<span class="hljs-comment">//   Error: Whoops, something bad happened</span>
<span class="hljs-comment">//     at [eval]:5:15</span>
<span class="hljs-comment">//     at Script.runInThisContext (node:vm:132:18)</span>
<span class="hljs-comment">//     at Object.runInThisContext (node:vm:309:38)</span>
<span class="hljs-comment">//     at node:internal/process/execution:77:19</span>
<span class="hljs-comment">//     at [eval]-wrapper:6:22</span>
<span class="hljs-comment">//     at evalScript (node:internal/process/execution:76:60)</span>
<span class="hljs-comment">//     at node:internal/main/eval_string:23:3</span>

<span class="hljs-keyword">const</span> name = <span class="hljs-string">'Will Robinson'</span>;
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">warn</span>(<span class="hljs-string">`Danger <span class="hljs-subst">${name}</span>! Danger!`</span>);
<span class="hljs-comment">// Prints: Danger Will Robinson! Danger!, to stderr</span></code></pre>
<p>Example using the <code>Console</code> class:</p>
<pre><code class="language-js"><span class="hljs-keyword">const</span> out = <span class="hljs-title function_">getStreamSomehow</span>();
<span class="hljs-keyword">const</span> err = <span class="hljs-title function_">getStreamSomehow</span>();
<span class="hljs-keyword">const</span> myConsole = <span class="hljs-keyword">new</span> <span class="hljs-variable language_">console</span>.<span class="hljs-title class_">Console</span>(out, err);

myConsole.<span class="hljs-title function_">log</span>(<span class="hljs-string">'hello world'</span>);
<span class="hljs-comment">// Prints: hello world, to out</span>
myConsole.<span class="hljs-title function_">log</span>(<span class="hljs-string">'hello %s'</span>, <span class="hljs-string">'world'</span>);
<span class="hljs-comment">// Prints: hello world, to out</span>
myConsole.<span class="hljs-title function_">error</span>(<span class="hljs-keyword">new</span> <span class="hljs-title class_">Error</span>(<span class="hljs-string">'Whoops, something bad happened'</span>));
<span class="hljs-comment">// Prints: [Error: Whoops, something bad happened], to err</span>

<span class="hljs-keyword">const</span> name = <span class="hljs-string">'Will Robinson'</span>;
myConsole.<span class="hljs-title function_">warn</span>(<span class="hljs-string">`Danger <span class="hljs-subst">${name}</span>! Danger!`</span>);
<span class="hljs-comment">// Prints: Danger Will Robinson! Danger!, to err</span></code></pre>
<section><h3>Class: <code>Console</code><span><a class="mark" href="#console_class_console" id="console_class_console">#</a></span></h3>
<div class="api_metadata">
<details class="changelog"><summary>History</summary>
<table>
<tbody><tr><th>Version</th><th>Changes</th></tr>
<tr><td>v8.0.0</td>
<td><p>Errors that occur while writing to the underlying streams will now be ignored by default.</p></td></tr>
</tbody></table>
</details>
</div>

<p>The <code>Console</code> class can be used to create a simple logger with configurable
output streams and can be accessed using either <code>require('console').Console</code>
or <code>console.Console</code> (or their destructured counterparts):</p>
<pre><code class="language-js"><span class="hljs-keyword">const</span> { <span class="hljs-title class_">Console</span> } = <span class="hljs-built_in">require</span>(<span class="hljs-string">'console'</span>);</code></pre>
<pre><code class="language-js"><span class="hljs-keyword">const</span> { <span class="hljs-title class_">Console</span> } = <span class="hljs-variable language_">console</span>;</code></pre>
<h4><code>new Console(stdout[, stderr][, ignoreErrors])</code><span><a class="mark" href="#console_new_console_stdout_stderr_ignoreerrors" id="console_new_console_stdout_stderr_ignoreerrors">#</a></span></h4>
<h4><code>new Console(options)</code><span><a class="mark" href="#console_new_console_options" id="console_new_console_options">#</a></span></h4>
<div class="api_metadata">
<details class="changelog"><summary>History</summary>
<table>
<tbody><tr><th>Version</th><th>Changes</th></tr>
<tr><td>v14.2.0</td>
<td><p>The <code>groupIndentation</code> option was introduced.</p></td></tr>
<tr><td>v11.7.0</td>
<td><p>The <code>inspectOptions</code> option is introduced.</p></td></tr>
<tr><td>v10.0.0</td>
<td><p>The <code>Console</code> constructor now supports an <code>options</code> argument, and the <code>colorMode</code> option was introduced.</p></td></tr>
<tr><td>v8.0.0</td>
<td><p>The <code>ignoreErrors</code> option was introduced.</p></td></tr>
</tbody></table>
</details>
</div>
<ul>
<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type">&#x3C;Object></a>
<ul>
<li><code>stdout</code> <a href="stream.html#stream_class_stream_writable" class="type">&#x3C;stream.Writable></a></li>
<li><code>stderr</code> <a href="stream.html#stream_class_stream_writable" class="type">&#x3C;stream.Writable></a></li>
<li><code>ignoreErrors</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type">&#x3C;boolean></a> Ignore errors when writing to the underlying
streams. <strong>Default:</strong> <code>true</code>.</li>
<li><code>colorMode</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type">&#x3C;boolean></a> | <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type">&#x3C;string></a> Set color support for this <code>Console</code> instance.
Setting to <code>true</code> enables coloring while inspecting values. Setting to
<code>false</code> disables coloring while inspecting values. Setting to
<code>'auto'</code> makes color support depend on the value of the <code>isTTY</code> property
and the value returned by <code>getColorDepth()</code> on the respective stream. This
option can not be used, if <code>inspectOptions.colors</code> is set as well.
<strong>Default:</strong> <code>'auto'</code>.</li>
<li><code>inspectOptions</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type">&#x3C;Object></a> Specifies options that are passed along to
<a href="util.html#util_util_inspect_object_options"><code>util.inspect()</code></a>.</li>
<li><code>groupIndentation</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type">&#x3C;number></a> Set group indentation.
<strong>Default:</strong> <code>2</code>.</li>
</ul>
</li>
</ul>
<p>Creates a new <code>Console</code> with one or two writable stream instances. <code>stdout</code> is a
writable stream to print log or info output. <code>stderr</code> is used for warning or
error output. If <code>stderr</code> is not provided, <code>stdout</code> is used for <code>stderr</code>.</p>
<pre><code class="language-js"><span class="hljs-keyword">const</span> output = fs.<span class="hljs-title function_">createWriteStream</span>(<span class="hljs-string">'./stdout.log'</span>);
<span class="hljs-keyword">const</span> errorOutput = fs.<span class="hljs-title function_">createWriteStream</span>(<span class="hljs-string">'./stderr.log'</span>);
<span class="hljs-comment">// Custom simple logger</span>
<span class="hljs-keyword">const</span> logger = <span class="hljs-keyword">new</span> <span class="hljs-title class_">Console</span>({ <span class="hljs-attr">stdout</span>: output, <span class="hljs-attr">stderr</span>: errorOutput });
<span class="hljs-comment">// use it like console</span>
<span class="hljs-keyword">const</span> count = <span class="hljs-number">5</span>;
logger.<span class="hljs-title function_">log</span>(<span class="hljs-string">'count: %d'</span>, count);
<span class="hljs-comment">// In stdout.log: count 5</span></code></pre>
<p>The global <code>console</code> is a special <code>Console</code> whose output is sent to
<a href="process.html#process_process_stdout"><code>process.stdout</code></a> and <a href="process.html#process_process_stderr"><code>process.stderr</code></a>. It is equivalent to calling:</p>
<pre><code class="language-js"><span class="hljs-keyword">new</span> <span class="hljs-title class_">Console</span>({ <span class="hljs-attr">stdout</span>: process.<span class="hljs-property">stdout</span>, <span class="hljs-attr">stderr</span>: process.<span class="hljs-property">stderr</span> });</code></pre>
<h4><code>console.assert(value[, ...message])</code><span><a class="mark" href="#console_console_assert_value_message" id="console_console_assert_value_message">#</a></span></h4>
<div class="api_metadata">
<details class="changelog"><summary>History</summary>
<table>
<tbody><tr><th>Version</th><th>Changes</th></tr>
<tr><td>v10.0.0</td>
<td><p>The implementation is now spec compliant and does not throw anymore.</p></td></tr>
<tr><td>v0.1.101</td>
<td><p><span>Added in: v0.1.101</span></p></td></tr>
</tbody></table>
</details>
</div>
<ul>
<li><code>value</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a> The value tested for being truthy.</li>
<li><code>...message</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a> All arguments besides <code>value</code> are used as error message.</li>
</ul>
<p><code>console.assert()</code> writes a message if <code>value</code> is <a href="https://developer.mozilla.org/en-US/docs/Glossary/Falsy">falsy</a> or omitted. It only
writes a message and does not otherwise affect execution. The output always
starts with <code>"Assertion failed"</code>. If provided, <code>message</code> is formatted using
<a href="util.html#util_util_format_format_args"><code>util.format()</code></a>.</p>
<p>If <code>value</code> is <a href="https://developer.mozilla.org/en-US/docs/Glossary/Truthy">truthy</a>, nothing happens.</p>
<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">assert</span>(<span class="hljs-literal">true</span>, <span class="hljs-string">'does nothing'</span>);

<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">assert</span>(<span class="hljs-literal">false</span>, <span class="hljs-string">'Whoops %s work'</span>, <span class="hljs-string">'didn\'t'</span>);
<span class="hljs-comment">// Assertion failed: Whoops didn't work</span>

<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">assert</span>();
<span class="hljs-comment">// Assertion failed</span></code></pre>
<h4><code>console.clear()</code><span><a class="mark" href="#console_console_clear" id="console_console_clear">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v8.3.0</span>
</div>
<p>When <code>stdout</code> is a TTY, calling <code>console.clear()</code> will attempt to clear the
TTY. When <code>stdout</code> is not a TTY, this method does nothing.</p>
<p>The specific operation of <code>console.clear()</code> can vary across operating systems
and terminal types. For most Linux operating systems, <code>console.clear()</code>
operates similarly to the <code>clear</code> shell command. On Windows, <code>console.clear()</code>
will clear only the output in the current terminal viewport for the Node.js
binary.</p>
<h4><code>console.count([label])</code><span><a class="mark" href="#console_console_count_label" id="console_console_count_label">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v8.3.0</span>
</div>
<ul>
<li><code>label</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type">&#x3C;string></a> The display label for the counter. <strong>Default:</strong> <code>'default'</code>.</li>
</ul>
<p>Maintains an internal counter specific to <code>label</code> and outputs to <code>stdout</code> the
number of times <code>console.count()</code> has been called with the given <code>label</code>.</p>
<!-- eslint-skip -->
<pre><code class="language-js">> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">count</span>()
<span class="hljs-attr">default</span>: <span class="hljs-number">1</span>
<span class="hljs-literal">undefined</span>
> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">count</span>(<span class="hljs-string">'default'</span>)
<span class="hljs-attr">default</span>: <span class="hljs-number">2</span>
<span class="hljs-literal">undefined</span>
> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">count</span>(<span class="hljs-string">'abc'</span>)
<span class="hljs-attr">abc</span>: <span class="hljs-number">1</span>
<span class="hljs-literal">undefined</span>
> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">count</span>(<span class="hljs-string">'xyz'</span>)
<span class="hljs-attr">xyz</span>: <span class="hljs-number">1</span>
<span class="hljs-literal">undefined</span>
> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">count</span>(<span class="hljs-string">'abc'</span>)
<span class="hljs-attr">abc</span>: <span class="hljs-number">2</span>
<span class="hljs-literal">undefined</span>
> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">count</span>()
<span class="hljs-attr">default</span>: <span class="hljs-number">3</span>
<span class="hljs-literal">undefined</span>
></code></pre>
<h4><code>console.countReset([label])</code><span><a class="mark" href="#console_console_countreset_label" id="console_console_countreset_label">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v8.3.0</span>
</div>
<ul>
<li><code>label</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type">&#x3C;string></a> The display label for the counter. <strong>Default:</strong> <code>'default'</code>.</li>
</ul>
<p>Resets the internal counter specific to <code>label</code>.</p>
<!-- eslint-skip -->
<pre><code class="language-js">> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">count</span>(<span class="hljs-string">'abc'</span>);
<span class="hljs-attr">abc</span>: <span class="hljs-number">1</span>
<span class="hljs-literal">undefined</span>
> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">countReset</span>(<span class="hljs-string">'abc'</span>);
<span class="hljs-literal">undefined</span>
> <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">count</span>(<span class="hljs-string">'abc'</span>);
<span class="hljs-attr">abc</span>: <span class="hljs-number">1</span>
<span class="hljs-literal">undefined</span>
></code></pre>
<h4><code>console.debug(data[, ...args])</code><span><a class="mark" href="#console_console_debug_data_args" id="console_console_debug_data_args">#</a></span></h4>
<div class="api_metadata">
<details class="changelog"><summary>History</summary>
<table>
<tbody><tr><th>Version</th><th>Changes</th></tr>
<tr><td>v8.10.0</td>
<td><p><code>console.debug</code> is now an alias for <code>console.log</code>.</p></td></tr>
<tr><td>v8.0.0</td>
<td><p><span>Added in: v8.0.0</span></p></td></tr>
</tbody></table>
</details>
</div>
<ul>
<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
<li><code>...args</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
</ul>
<p>The <code>console.debug()</code> function is an alias for <a href="#console_console_log_data_args"><code>console.log()</code></a>.</p>
<h4><code>console.dir(obj[, options])</code><span><a class="mark" href="#console_console_dir_obj_options" id="console_console_dir_obj_options">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v0.1.101</span>
</div>
<ul>
<li><code>obj</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
<li><code>options</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object" class="type">&#x3C;Object></a>
<ul>
<li><code>showHidden</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type">&#x3C;boolean></a> If <code>true</code> then the object's non-enumerable and symbol
properties will be shown too. <strong>Default:</strong> <code>false</code>.</li>
<li><code>depth</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Number_type" class="type">&#x3C;number></a> Tells <a href="util.html#util_util_inspect_object_options"><code>util.inspect()</code></a> how many times to recurse while
formatting the object. This is useful for inspecting large complicated
objects. To make it recurse indefinitely, pass <code>null</code>. <strong>Default:</strong> <code>2</code>.</li>
<li><code>colors</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type" class="type">&#x3C;boolean></a> If <code>true</code>, then the output will be styled with ANSI color
codes. Colors are customizable;
see <a href="util.html#util_customizing_util_inspect_colors">customizing <code>util.inspect()</code> colors</a>. <strong>Default:</strong> <code>false</code>.</li>
</ul>
</li>
</ul>
<p>Uses <a href="util.html#util_util_inspect_object_options"><code>util.inspect()</code></a> on <code>obj</code> and prints the resulting string to <code>stdout</code>.
This function bypasses any custom <code>inspect()</code> function defined on <code>obj</code>.</p>
<h4><code>console.dirxml(...data)</code><span><a class="mark" href="#console_console_dirxml_data" id="console_console_dirxml_data">#</a></span></h4>
<div class="api_metadata">
<details class="changelog"><summary>History</summary>
<table>
<tbody><tr><th>Version</th><th>Changes</th></tr>
<tr><td>v9.3.0</td>
<td><p><code>console.dirxml</code> now calls <code>console.log</code> for its arguments.</p></td></tr>
<tr><td>v8.0.0</td>
<td><p><span>Added in: v8.0.0</span></p></td></tr>
</tbody></table>
</details>
</div>
<ul>
<li><code>...data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
</ul>
<p>This method calls <code>console.log()</code> passing it the arguments received.
This method does not produce any XML formatting.</p>
<h4><code>console.error([data][, ...args])</code><span><a class="mark" href="#console_console_error_data_args" id="console_console_error_data_args">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v0.1.100</span>
</div>
<ul>
<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
<li><code>...args</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
</ul>
<p>Prints to <code>stderr</code> with newline. Multiple arguments can be passed, with the
first used as the primary message and all additional used as substitution
values similar to <a href="http://man7.org/linux/man-pages/man3/printf.3.html"><code>printf(3)</code></a> (the arguments are all passed to
<a href="util.html#util_util_format_format_args"><code>util.format()</code></a>).</p>
<pre><code class="language-js"><span class="hljs-keyword">const</span> code = <span class="hljs-number">5</span>;
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'error #%d'</span>, code);
<span class="hljs-comment">// Prints: error #5, to stderr</span>
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">error</span>(<span class="hljs-string">'error'</span>, code);
<span class="hljs-comment">// Prints: error 5, to stderr</span></code></pre>
<p>If formatting elements (e.g. <code>%d</code>) are not found in the first string then
<a href="util.html#util_util_inspect_object_options"><code>util.inspect()</code></a> is called on each argument and the resulting string
values are concatenated. See <a href="util.html#util_util_format_format_args"><code>util.format()</code></a> for more information.</p>
<h4><code>console.group([...label])</code><span><a class="mark" href="#console_console_group_label" id="console_console_group_label">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v8.5.0</span>
</div>
<ul>
<li><code>...label</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
</ul>
<p>Increases indentation of subsequent lines by spaces for <code>groupIndentation</code>
length.</p>
<p>If one or more <code>label</code>s are provided, those are printed first without the
additional indentation.</p>
<h4><code>console.groupCollapsed()</code><span><a class="mark" href="#console_console_groupcollapsed" id="console_console_groupcollapsed">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v8.5.0</span>
</div>
<p>An alias for <a href="#console_console_group_label"><code>console.group()</code></a>.</p>
<h4><code>console.groupEnd()</code><span><a class="mark" href="#console_console_groupend" id="console_console_groupend">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v8.5.0</span>
</div>
<p>Decreases indentation of subsequent lines by spaces for <code>groupIndentation</code>
length.</p>
<h4><code>console.info([data][, ...args])</code><span><a class="mark" href="#console_console_info_data_args" id="console_console_info_data_args">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v0.1.100</span>
</div>
<ul>
<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
<li><code>...args</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
</ul>
<p>The <code>console.info()</code> function is an alias for <a href="#console_console_log_data_args"><code>console.log()</code></a>.</p>
<h4><code>console.log([data][, ...args])</code><span><a class="mark" href="#console_console_log_data_args" id="console_console_log_data_args">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v0.1.100</span>
</div>
<ul>
<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
<li><code>...args</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
</ul>
<p>Prints to <code>stdout</code> with newline. Multiple arguments can be passed, with the
first used as the primary message and all additional used as substitution
values similar to <a href="http://man7.org/linux/man-pages/man3/printf.3.html"><code>printf(3)</code></a> (the arguments are all passed to
<a href="util.html#util_util_format_format_args"><code>util.format()</code></a>).</p>
<pre><code class="language-js"><span class="hljs-keyword">const</span> count = <span class="hljs-number">5</span>;
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'count: %d'</span>, count);
<span class="hljs-comment">// Prints: count: 5, to stdout</span>
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">'count:'</span>, count);
<span class="hljs-comment">// Prints: count: 5, to stdout</span></code></pre>
<p>See <a href="util.html#util_util_format_format_args"><code>util.format()</code></a> for more information.</p>
<h4><code>console.table(tabularData[, properties])</code><span><a class="mark" href="#console_console_table_tabulardata_properties" id="console_console_table_tabulardata_properties">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v10.0.0</span>
</div>
<ul>
<li><code>tabularData</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
<li><code>properties</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type">&#x3C;string[]></a> Alternate properties for constructing the table.</li>
</ul>
<p>Try to construct a table with the columns of the properties of <code>tabularData</code>
(or use <code>properties</code>) and rows of <code>tabularData</code> and log it. Falls back to just
logging the argument if it can’t be parsed as tabular.</p>
<pre><code class="language-js"><span class="hljs-comment">// These can't be parsed as tabular data</span>
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">table</span>(<span class="hljs-title class_">Symbol</span>());
<span class="hljs-comment">// Symbol()</span>

<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">table</span>(<span class="hljs-literal">undefined</span>);
<span class="hljs-comment">// undefined</span>

<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">table</span>([{ <span class="hljs-attr">a</span>: <span class="hljs-number">1</span>, <span class="hljs-attr">b</span>: <span class="hljs-string">'Y'</span> }, { <span class="hljs-attr">a</span>: <span class="hljs-string">'Z'</span>, <span class="hljs-attr">b</span>: <span class="hljs-number">2</span> }]);
<span class="hljs-comment">// ┌─────────┬─────┬─────┐</span>
<span class="hljs-comment">// │ (index) │  a  │  b  │</span>
<span class="hljs-comment">// ├─────────┼─────┼─────┤</span>
<span class="hljs-comment">// │    0    │  1  │ 'Y' │</span>
<span class="hljs-comment">// │    1    │ 'Z' │  2  │</span>
<span class="hljs-comment">// └─────────┴─────┴─────┘</span>

<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">table</span>([{ <span class="hljs-attr">a</span>: <span class="hljs-number">1</span>, <span class="hljs-attr">b</span>: <span class="hljs-string">'Y'</span> }, { <span class="hljs-attr">a</span>: <span class="hljs-string">'Z'</span>, <span class="hljs-attr">b</span>: <span class="hljs-number">2</span> }], [<span class="hljs-string">'a'</span>]);
<span class="hljs-comment">// ┌─────────┬─────┐</span>
<span class="hljs-comment">// │ (index) │  a  │</span>
<span class="hljs-comment">// ├─────────┼─────┤</span>
<span class="hljs-comment">// │    0    │  1  │</span>
<span class="hljs-comment">// │    1    │ 'Z' │</span>
<span class="hljs-comment">// └─────────┴─────┘</span></code></pre>
<h4><code>console.time([label])</code><span><a class="mark" href="#console_console_time_label" id="console_console_time_label">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v0.1.104</span>
</div>
<ul>
<li><code>label</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type">&#x3C;string></a> <strong>Default:</strong> <code>'default'</code></li>
</ul>
<p>Starts a timer that can be used to compute the duration of an operation. Timers
are identified by a unique <code>label</code>. Use the same <code>label</code> when calling
<a href="#console_console_timeend_label"><code>console.timeEnd()</code></a> to stop the timer and output the elapsed time in
suitable time units to <code>stdout</code>. For example, if the elapsed
time is 3869ms, <code>console.timeEnd()</code> displays "3.869s".</p>
<h4><code>console.timeEnd([label])</code><span><a class="mark" href="#console_console_timeend_label" id="console_console_timeend_label">#</a></span></h4>
<div class="api_metadata">
<details class="changelog"><summary>History</summary>
<table>
<tbody><tr><th>Version</th><th>Changes</th></tr>
<tr><td>v13.0.0</td>
<td><p>The elapsed time is displayed with a suitable time unit.</p></td></tr>
<tr><td>v6.0.0</td>
<td><p>This method no longer supports multiple calls that don’t map to individual <code>console.time()</code> calls; see below for details.</p></td></tr>
<tr><td>v0.1.104</td>
<td><p><span>Added in: v0.1.104</span></p></td></tr>
</tbody></table>
</details>
</div>
<ul>
<li><code>label</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type">&#x3C;string></a> <strong>Default:</strong> <code>'default'</code></li>
</ul>
<p>Stops a timer that was previously started by calling <a href="#console_console_time_label"><code>console.time()</code></a> and
prints the result to <code>stdout</code>:</p>
<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">time</span>(<span class="hljs-string">'100-elements'</span>);
<span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i &#x3C; <span class="hljs-number">100</span>; i++) {}
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">timeEnd</span>(<span class="hljs-string">'100-elements'</span>);
<span class="hljs-comment">// prints 100-elements: 225.438ms</span></code></pre>
<h4><code>console.timeLog([label][, ...data])</code><span><a class="mark" href="#console_console_timelog_label_data" id="console_console_timelog_label_data">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v10.7.0</span>
</div>
<ul>
<li><code>label</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type">&#x3C;string></a> <strong>Default:</strong> <code>'default'</code></li>
<li><code>...data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
</ul>
<p>For a timer that was previously started by calling <a href="#console_console_time_label"><code>console.time()</code></a>, prints
the elapsed time and other <code>data</code> arguments to <code>stdout</code>:</p>
<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">time</span>(<span class="hljs-string">'process'</span>);
<span class="hljs-keyword">const</span> value = <span class="hljs-title function_">expensiveProcess1</span>(); <span class="hljs-comment">// Returns 42</span>
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">timeLog</span>(<span class="hljs-string">'process'</span>, value);
<span class="hljs-comment">// Prints "process: 365.227ms 42".</span>
<span class="hljs-title function_">doExpensiveProcess2</span>(value);
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">timeEnd</span>(<span class="hljs-string">'process'</span>);</code></pre>
<h4><code>console.trace([message][, ...args])</code><span><a class="mark" href="#console_console_trace_message_args" id="console_console_trace_message_args">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v0.1.104</span>
</div>
<ul>
<li><code>message</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
<li><code>...args</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
</ul>
<p>Prints to <code>stderr</code> the string <code>'Trace: '</code>, followed by the <a href="util.html#util_util_format_format_args"><code>util.format()</code></a>
formatted message and stack trace to the current position in the code.</p>
<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">trace</span>(<span class="hljs-string">'Show me'</span>);
<span class="hljs-comment">// Prints: (stack trace will vary based on where trace is called)</span>
<span class="hljs-comment">//  Trace: Show me</span>
<span class="hljs-comment">//    at repl:2:9</span>
<span class="hljs-comment">//    at REPLServer.defaultEval (repl.js:248:27)</span>
<span class="hljs-comment">//    at bound (domain.js:287:14)</span>
<span class="hljs-comment">//    at REPLServer.runBound [as eval] (domain.js:300:12)</span>
<span class="hljs-comment">//    at REPLServer.&#x3C;anonymous> (repl.js:412:12)</span>
<span class="hljs-comment">//    at emitOne (events.js:82:20)</span>
<span class="hljs-comment">//    at REPLServer.emit (events.js:169:7)</span>
<span class="hljs-comment">//    at REPLServer.Interface._onLine (readline.js:210:10)</span>
<span class="hljs-comment">//    at REPLServer.Interface._line (readline.js:549:8)</span>
<span class="hljs-comment">//    at REPLServer.Interface._ttyWrite (readline.js:826:14)</span></code></pre>
<h4><code>console.warn([data][, ...args])</code><span><a class="mark" href="#console_console_warn_data_args" id="console_console_warn_data_args">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v0.1.100</span>
</div>
<ul>
<li><code>data</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
<li><code>...args</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types" class="type">&#x3C;any></a></li>
</ul>
<p>The <code>console.warn()</code> function is an alias for <a href="#console_console_error_data_args"><code>console.error()</code></a>.</p>
</section><section><h3>Inspector only methods<span><a class="mark" href="#console_inspector_only_methods" id="console_inspector_only_methods">#</a></span></h3>
<p>The following methods are exposed by the V8 engine in the general API but do
not display anything unless used in conjunction with the <a href="debugger.html">inspector</a>
(<code>--inspect</code> flag).</p>
<h4><code>console.profile([label])</code><span><a class="mark" href="#console_console_profile_label" id="console_console_profile_label">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v8.0.0</span>
</div>
<ul>
<li><code>label</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type">&#x3C;string></a></li>
</ul>
<p>This method does not display anything unless used in the inspector. The
<code>console.profile()</code> method starts a JavaScript CPU profile with an optional
label until <a href="#console_console_profileend_label"><code>console.profileEnd()</code></a> is called. The profile is then added to
the <strong>Profile</strong> panel of the inspector.</p>
<pre><code class="language-js"><span class="hljs-variable language_">console</span>.<span class="hljs-title function_">profile</span>(<span class="hljs-string">'MyLabel'</span>);
<span class="hljs-comment">// Some code</span>
<span class="hljs-variable language_">console</span>.<span class="hljs-title function_">profileEnd</span>(<span class="hljs-string">'MyLabel'</span>);
<span class="hljs-comment">// Adds the profile 'MyLabel' to the Profiles panel of the inspector.</span></code></pre>
<h4><code>console.profileEnd([label])</code><span><a class="mark" href="#console_console_profileend_label" id="console_console_profileend_label">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v8.0.0</span>
</div>
<ul>
<li><code>label</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type">&#x3C;string></a></li>
</ul>
<p>This method does not display anything unless used in the inspector. Stops the
current JavaScript CPU profiling session if one has been started and prints
the report to the <strong>Profiles</strong> panel of the inspector. See
<a href="#console_console_profile_label"><code>console.profile()</code></a> for an example.</p>
<p>If this method is called without a label, the most recently started profile is
stopped.</p>
<h4><code>console.timeStamp([label])</code><span><a class="mark" href="#console_console_timestamp_label" id="console_console_timestamp_label">#</a></span></h4>
<div class="api_metadata">
<span>Added in: v8.0.0</span>
</div>
<ul>
<li><code>label</code> <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type" class="type">&#x3C;string></a></li>
</ul>
<p>This method does not display anything unless used in the inspector. The
<code>console.timeStamp()</code> method adds an event with the label <code>'label'</code> to the
<strong>Timeline</strong> panel of the inspector.</p></section>
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