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<h1>Node.js v0.10.29 Manual & Documentation</h1>
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<h2>Table of Contents</h2>
<ul>
<li><a href="#console_console">console</a><ul>
<li><a href="#console_console_log_data">console.log([data], [...])</a></li>
<li><a href="#console_console_info_data">console.info([data], [...])</a></li>
<li><a href="#console_console_error_data">console.error([data], [...])</a></li>
<li><a href="#console_console_warn_data">console.warn([data], [...])</a></li>
<li><a href="#console_console_dir_obj">console.dir(obj)</a></li>
<li><a href="#console_console_time_label">console.time(label)</a></li>
<li><a href="#console_console_timeend_label">console.timeEnd(label)</a></li>
<li><a href="#console_console_trace_label">console.trace(label)</a></li>
<li><a href="#console_console_assert_expression_message">console.assert(expression, [message])</a></li>
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<div id="apicontent">
<h1>console<span><a class="mark" href="#console_console" id="console_console">#</a></span></h1>
<pre class="api_stability_4">Stability: 4 - API Frozen</pre><div class="signature"><ul>
<li><span class="type">Object</span></li>
</div></ul>
<!--type=global-->
<p>For printing to stdout and stderr. Similar to the console object functions
provided by most web browsers, here the output is sent to stdout or stderr.
</p>
<p>The console functions are synchronous when the destination is a terminal or
a file (to avoid lost messages in case of premature exit) and asynchronous
when it's a pipe (to avoid blocking for long periods of time).
</p>
<p>That is, in the following example, stdout is non-blocking while stderr
is blocking:
</p>
<pre><code>$ node script.js 2> error.log | tee info.log</code></pre>
<p>In daily use, the blocking/non-blocking dichotomy is not something you
should worry about unless you log huge amounts of data.
</p>
<h2>console.log([data], [...])<span><a class="mark" href="#console_console_log_data" id="console_console_log_data">#</a></span></h2>
<p>Prints to stdout with newline. This function can take multiple arguments in a
<code>printf()</code>-like way. Example:
</p>
<pre><code>console.log('count: %d', count);</code></pre>
<p>If formatting elements are not found in the first string then <code>util.inspect</code>
is used on each argument. See <a href="util.html#util_util_format_format">util.format()</a> for more information.
</p>
<h2>console.info([data], [...])<span><a class="mark" href="#console_console_info_data" id="console_console_info_data">#</a></span></h2>
<p>Same as <code>console.log</code>.
</p>
<h2>console.error([data], [...])<span><a class="mark" href="#console_console_error_data" id="console_console_error_data">#</a></span></h2>
<p>Same as <code>console.log</code> but prints to stderr.
</p>
<h2>console.warn([data], [...])<span><a class="mark" href="#console_console_warn_data" id="console_console_warn_data">#</a></span></h2>
<p>Same as <code>console.error</code>.
</p>
<h2>console.dir(obj)<span><a class="mark" href="#console_console_dir_obj" id="console_console_dir_obj">#</a></span></h2>
<p>Uses <code>util.inspect</code> on <code>obj</code> and prints resulting string to stdout.
</p>
<h2>console.time(label)<span><a class="mark" href="#console_console_time_label" id="console_console_time_label">#</a></span></h2>
<p>Mark a time.
</p>
<h2>console.timeEnd(label)<span><a class="mark" href="#console_console_timeend_label" id="console_console_timeend_label">#</a></span></h2>
<p>Finish timer, record output. Example:
</p>
<pre><code>console.time('100-elements');
for (var i = 0; i < 100; i++) {
;
}
console.timeEnd('100-elements');</code></pre>
<h2>console.trace(label)<span><a class="mark" href="#console_console_trace_label" id="console_console_trace_label">#</a></span></h2>
<p>Print a stack trace to stderr of the current position.
</p>
<h2>console.assert(expression, [message])<span><a class="mark" href="#console_console_assert_expression_message" id="console_console_assert_expression_message">#</a></span></h2>
<p>Same as <a href="assert.html#assert_assert_value_message_assert_ok_value_message">assert.ok()</a> where if the <code>expression</code> evaluates as <code>false</code> throw an
AssertionError with <code>message</code>.
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