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           <div id="toc">
             <h2>Table of Contents</h2>
             <ul>
 <li><a href="#util_util">util</a><ul>
 <li><a href="#util_util_format_format">util.format(format, [...])</a></li>
 <li><a href="#util_util_debug_string">util.debug(string)</a></li>
 <li><a href="#util_util_error">util.error([...])</a></li>
 <li><a href="#util_util_puts">util.puts([...])</a></li>
 <li><a href="#util_util_print">util.print([...])</a></li>
 <li><a href="#util_util_log_string">util.log(string)</a></li>
 <li><a href="#util_util_inspect_object_options">util.inspect(object, [options])</a><ul>
 <li><a href="#util_customizing_util_inspect_colors">Customizing <code>util.inspect</code> colors</a></li>
 </ul>
 </li>
 <li><a href="#util_util_isarray_object">util.isArray(object)</a></li>
 <li><a href="#util_util_isregexp_object">util.isRegExp(object)</a></li>
 <li><a href="#util_util_isdate_object">util.isDate(object)</a></li>
 <li><a href="#util_util_iserror_object">util.isError(object)</a></li>
 <li><a href="#util_util_pump_readablestream_writablestream_callback">util.pump(readableStream, writableStream, [callback])</a></li>
 <li><a href="#util_util_inherits_constructor_superconstructor">util.inherits(constructor, superConstructor)</a></li>
 </ul>
 </li>
 </ul>

           </div>

           <div id="apicontent">
             <h1>util<span><a class="mark" href="#util_util" id="util_util">#</a></span></h1>
 <pre class="api_stability_4">Stability: 4 - API Frozen</pre><p>These functions are in the module <code>&#39;util&#39;</code>. Use <code>require(&#39;util&#39;)</code> to access
 them.


 </p>
 <h2>util.format(format, [...])<span><a class="mark" href="#util_util_format_format" id="util_util_format_format">#</a></span></h2>
 <p>Returns a formatted string using the first argument as a <code>printf</code>-like format.

 </p>
 <p>The first argument is a string that contains zero or more <em>placeholders</em>.
 Each placeholder is replaced with the converted value from its corresponding
 argument. Supported placeholders are:

 </p>
 <ul>
 <li><code>%s</code> - String.</li>
 <li><code>%d</code> - Number (both integer and float).</li>
 <li><code>%j</code> - JSON.</li>
 <li><code>%</code> - single percent sign (<code>&#39;%&#39;</code>). This does not consume an argument.</li>
 </ul>
 <p>If the placeholder does not have a corresponding argument, the placeholder is
 not replaced.

 </p>
 <pre><code>util.format(&#39;%s:%s&#39;, &#39;foo&#39;); // &#39;foo:%s&#39;</code></pre>
 <p>If there are more arguments than placeholders, the extra arguments are
 converted to strings with <code>util.inspect()</code> and these strings are concatenated,
 delimited by a space.

 </p>
 <pre><code>util.format(&#39;%s:%s&#39;, &#39;foo&#39;, &#39;bar&#39;, &#39;baz&#39;); // &#39;foo:bar baz&#39;</code></pre>
 <p>If the first argument is not a format string then <code>util.format()</code> returns
 a string that is the concatenation of all its arguments separated by spaces.
 Each argument is converted to a string with <code>util.inspect()</code>.

 </p>
 <pre><code>util.format(1, 2, 3); // &#39;1 2 3&#39;</code></pre>
 <h2>util.debug(string)<span><a class="mark" href="#util_util_debug_string" id="util_util_debug_string">#</a></span></h2>
 <p>A synchronous output function. Will block the process and
 output <code>string</code> immediately to <code>stderr</code>.

 </p>
 <pre><code>require(&#39;util&#39;).debug(&#39;message on stderr&#39;);</code></pre>
 <h2>util.error([...])<span><a class="mark" href="#util_util_error" id="util_util_error">#</a></span></h2>
 <p>Same as <code>util.debug()</code> except this will output all arguments immediately to
 <code>stderr</code>.

 </p>
 <h2>util.puts([...])<span><a class="mark" href="#util_util_puts" id="util_util_puts">#</a></span></h2>
 <p>A synchronous output function. Will block the process and output all arguments
 to <code>stdout</code> with newlines after each argument.

 </p>
 <h2>util.print([...])<span><a class="mark" href="#util_util_print" id="util_util_print">#</a></span></h2>
 <p>A synchronous output function. Will block the process, cast each argument to a
 string then output to <code>stdout</code>. Does not place newlines after each argument.

 </p>
 <h2>util.log(string)<span><a class="mark" href="#util_util_log_string" id="util_util_log_string">#</a></span></h2>
 <p>Output with timestamp on <code>stdout</code>.

 </p>
 <pre><code>require(&#39;util&#39;).log(&#39;Timestamped message.&#39;);</code></pre>
 <h2>util.inspect(object, [options])<span><a class="mark" href="#util_util_inspect_object_options" id="util_util_inspect_object_options">#</a></span></h2>
 <p>Return a string representation of <code>object</code>, which is useful for debugging.

 </p>
 <p>An optional <em>options</em> object may be passed that alters certain aspects of the
 formatted string:

 </p>
 <ul>
 <li><p><code>showHidden</code> - if <code>true</code> then the object&#39;s non-enumerable properties will be
 shown too. Defaults to <code>false</code>.</p>
 </li>
 <li><p><code>depth</code> - tells <code>inspect</code> how many times to recurse while formatting the
 object. This is useful for inspecting large complicated objects. Defaults to
 <code>2</code>. To make it recurse indefinitely pass <code>null</code>.</p>
 </li>
 <li><p><code>colors</code> - if <code>true</code>, then the output will be styled with ANSI color codes.
 Defaults to <code>false</code>. Colors are customizable, see below.</p>
 </li>
 <li><p><code>customInspect</code> - if <code>false</code>, then custom <code>inspect()</code> functions defined on the
 objects being inspected won&#39;t be called. Defaults to <code>true</code>.</p>
 </li>
 </ul>
 <p>Example of inspecting all properties of the <code>util</code> object:

 </p>
 <pre><code>var util = require(&#39;util&#39;);

 console.log(util.inspect(util, { showHidden: true, depth: null }));</code></pre>
 <h3>Customizing <code>util.inspect</code> colors<span><a class="mark" href="#util_customizing_util_inspect_colors" id="util_customizing_util_inspect_colors">#</a></span></h3>
 <p>Color output (if enabled) of <code>util.inspect</code> is customizable globally
 via <code>util.inspect.styles</code> and <code>util.inspect.colors</code> objects.

 </p>
 <p><code>util.inspect.styles</code> is a map assigning each style a color
 from <code>util.inspect.colors</code>.
 Highlighted styles and their default values are:
  <em> <code>number</code> (yellow)
  </em> <code>boolean</code> (yellow)
  <em> <code>string</code> (green)
  </em> <code>date</code> (magenta)
  <em> <code>regexp</code> (red)
  </em> <code>null</code> (bold)
  <em> <code>undefined</code> (grey)
  </em> <code>special</code> - only function at this time (cyan)
  * <code>name</code> (intentionally no styling)

 </p>
 <p>Predefined color codes are: <code>white</code>, <code>grey</code>, <code>black</code>, <code>blue</code>, <code>cyan</code>,
 <code>green</code>, <code>magenta</code>, <code>red</code> and <code>yellow</code>.
 There are also <code>bold</code>, <code>italic</code>, <code>underline</code> and <code>inverse</code> codes.

 </p>
 <p>Objects also may define their own <code>inspect(depth)</code> function which <code>util.inspect()</code>
 will invoke and use the result of when inspecting the object:

 </p>
 <pre><code>var util = require(&#39;util&#39;);

 var obj = { name: &#39;nate&#39; };
 obj.inspect = function(depth) {
   return &#39;{&#39; + this.name + &#39;}&#39;;
 };

 util.inspect(obj);
   // &quot;{nate}&quot;</code></pre>
 <h2>util.isArray(object)<span><a class="mark" href="#util_util_isarray_object" id="util_util_isarray_object">#</a></span></h2>
 <p>Returns <code>true</code> if the given &quot;object&quot; is an <code>Array</code>. <code>false</code> otherwise.

 </p>
 <pre><code>var util = require(&#39;util&#39;);

 util.isArray([])
   // true
 util.isArray(new Array)
   // true
 util.isArray({})
   // false</code></pre>
 <h2>util.isRegExp(object)<span><a class="mark" href="#util_util_isregexp_object" id="util_util_isregexp_object">#</a></span></h2>
 <p>Returns <code>true</code> if the given &quot;object&quot; is a <code>RegExp</code>. <code>false</code> otherwise.

 </p>
 <pre><code>var util = require(&#39;util&#39;);

 util.isRegExp(/some regexp/)
   // true
 util.isRegExp(new RegExp(&#39;another regexp&#39;))
   // true
 util.isRegExp({})
   // false</code></pre>
 <h2>util.isDate(object)<span><a class="mark" href="#util_util_isdate_object" id="util_util_isdate_object">#</a></span></h2>
 <p>Returns <code>true</code> if the given &quot;object&quot; is a <code>Date</code>. <code>false</code> otherwise.

 </p>
 <pre><code>var util = require(&#39;util&#39;);

 util.isDate(new Date())
   // true
 util.isDate(Date())
   // false (without &#39;new&#39; returns a String)
 util.isDate({})
   // false</code></pre>
 <h2>util.isError(object)<span><a class="mark" href="#util_util_iserror_object" id="util_util_iserror_object">#</a></span></h2>
 <p>Returns <code>true</code> if the given &quot;object&quot; is an <code>Error</code>. <code>false</code> otherwise.

 </p>
 <pre><code>var util = require(&#39;util&#39;);

 util.isError(new Error())
   // true
 util.isError(new TypeError())
   // true
 util.isError({ name: &#39;Error&#39;, message: &#39;an error occurred&#39; })
   // false</code></pre>
 <h2>util.pump(readableStream, writableStream, [callback])<span><a class="mark" href="#util_util_pump_readablestream_writablestream_callback" id="util_util_pump_readablestream_writablestream_callback">#</a></span></h2>
 <pre class="api_stability_0">Stability: 0 - Deprecated: Use readableStream.pipe(writableStream)</pre><p>Read the data from <code>readableStream</code> and send it to the <code>writableStream</code>.
 When <code>writableStream.write(data)</code> returns <code>false</code> <code>readableStream</code> will be
 paused until the <code>drain</code> event occurs on the <code>writableStream</code>. <code>callback</code> gets
 an error as its only argument and is called when <code>writableStream</code> is closed or
 when an error occurs.


 </p>
 <h2>util.inherits(constructor, superConstructor)<span><a class="mark" href="#util_util_inherits_constructor_superconstructor" id="util_util_inherits_constructor_superconstructor">#</a></span></h2>
 <p>Inherit the prototype methods from one
 <a href="https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Object/constructor">constructor</a>
 into another.  The prototype of <code>constructor</code> will be set to a new
 object created from <code>superConstructor</code>.

 </p>
 <p>As an additional convenience, <code>superConstructor</code> will be accessible
 through the <code>constructor.super_</code> property.

 </p>
 <pre><code>var util = require(&quot;util&quot;);
 var events = require(&quot;events&quot;);

 function MyStream() {
     events.EventEmitter.call(this);
 }

 util.inherits(MyStream, events.EventEmitter);

 MyStream.prototype.write = function(data) {
     this.emit(&quot;data&quot;, data);
 }

 var stream = new MyStream();

 console.log(stream instanceof events.EventEmitter); // true
 console.log(MyStream.super_ === events.EventEmitter); // true

 stream.on(&quot;data&quot;, function(data) {
     console.log(&#39;Received data: &quot;&#39; + data + &#39;&quot;&#39;);
 })
 stream.write(&quot;It works!&quot;); // Received data: &quot;It works!&quot;</code></pre>

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	</header>

	<div id="toc">
	<h2>Table of Contents</h2>
	<ul>
	<li><a href="#util_util">util</a><ul>
	<li><a href="#util_util_format_format">util.format(format, [...])</a></li>
	<li><a href="#util_util_debug_string">util.debug(string)</a></li>
	<li><a href="#util_util_error">util.error([...])</a></li>
	<li><a href="#util_util_puts">util.puts([...])</a></li>
	<li><a href="#util_util_print">util.print([...])</a></li>
	<li><a href="#util_util_log_string">util.log(string)</a></li>
	<li><a href="#util_util_inspect_object_options">util.inspect(object, [options])</a><ul>
	<li><a href="#util_customizing_util_inspect_colors">Customizing <code>util.inspect</code> colors</a></li>
	</ul>
	</li>
	<li><a href="#util_util_isarray_object">util.isArray(object)</a></li>
	<li><a href="#util_util_isregexp_object">util.isRegExp(object)</a></li>
	<li><a href="#util_util_isdate_object">util.isDate(object)</a></li>
	<li><a href="#util_util_iserror_object">util.isError(object)</a></li>
	<li><a href="#util_util_pump_readablestream_writablestream_callback">util.pump(readableStream, writableStream, [callback])</a></li>
	<li><a href="#util_util_inherits_constructor_superconstructor">util.inherits(constructor, superConstructor)</a></li>
	</ul>
	</li>
	</ul>

	</div>

	<div id="apicontent">
	<h1>util<span><a class="mark" href="#util_util" id="util_util">#</a></span></h1>
	<pre class="api_stability_4">Stability: 4 - API Frozen</pre><p>These functions are in the module <code>'util'</code>. Use <code>require('util')</code> to access
	them.


	</p>
	<h2>util.format(format, [...])<span><a class="mark" href="#util_util_format_format" id="util_util_format_format">#</a></span></h2>
	<p>Returns a formatted string using the first argument as a <code>printf</code>-like format.

	</p>
	<p>The first argument is a string that contains zero or more <em>placeholders</em>.
	Each placeholder is replaced with the converted value from its corresponding
	argument. Supported placeholders are:

	</p>
	<ul>
	<li><code>%s</code> - String.</li>
	<li><code>%d</code> - Number (both integer and float).</li>
	<li><code>%j</code> - JSON.</li>
	<li><code>%</code> - single percent sign (<code>'%'</code>). This does not consume an argument.</li>
	</ul>
	<p>If the placeholder does not have a corresponding argument, the placeholder is
	not replaced.

	</p>
	<pre><code>util.format('%s:%s', 'foo'); // 'foo:%s'</code></pre>
	<p>If there are more arguments than placeholders, the extra arguments are
	converted to strings with <code>util.inspect()</code> and these strings are concatenated,
	delimited by a space.

	</p>
	<pre><code>util.format('%s:%s', 'foo', 'bar', 'baz'); // 'foo:bar baz'</code></pre>
	<p>If the first argument is not a format string then <code>util.format()</code> returns
	a string that is the concatenation of all its arguments separated by spaces.
	Each argument is converted to a string with <code>util.inspect()</code>.

	</p>
	<pre><code>util.format(1, 2, 3); // '1 2 3'</code></pre>
	<h2>util.debug(string)<span><a class="mark" href="#util_util_debug_string" id="util_util_debug_string">#</a></span></h2>
	<p>A synchronous output function. Will block the process and
	output <code>string</code> immediately to <code>stderr</code>.

	</p>
	<pre><code>require('util').debug('message on stderr');</code></pre>
	<h2>util.error([...])<span><a class="mark" href="#util_util_error" id="util_util_error">#</a></span></h2>
	<p>Same as <code>util.debug()</code> except this will output all arguments immediately to
	<code>stderr</code>.

	</p>
	<h2>util.puts([...])<span><a class="mark" href="#util_util_puts" id="util_util_puts">#</a></span></h2>
	<p>A synchronous output function. Will block the process and output all arguments
	to <code>stdout</code> with newlines after each argument.

	</p>
	<h2>util.print([...])<span><a class="mark" href="#util_util_print" id="util_util_print">#</a></span></h2>
	<p>A synchronous output function. Will block the process, cast each argument to a
	string then output to <code>stdout</code>. Does not place newlines after each argument.

	</p>
	<h2>util.log(string)<span><a class="mark" href="#util_util_log_string" id="util_util_log_string">#</a></span></h2>
	<p>Output with timestamp on <code>stdout</code>.

	</p>
	<pre><code>require('util').log('Timestamped message.');</code></pre>
	<h2>util.inspect(object, [options])<span><a class="mark" href="#util_util_inspect_object_options" id="util_util_inspect_object_options">#</a></span></h2>
	<p>Return a string representation of <code>object</code>, which is useful for debugging.

	</p>
	<p>An optional <em>options</em> object may be passed that alters certain aspects of the
	formatted string:

	</p>
	<ul>
	<li><p><code>showHidden</code> - if <code>true</code> then the object's non-enumerable properties will be
	shown too. Defaults to <code>false</code>.</p>
	</li>
	<li><p><code>depth</code> - tells <code>inspect</code> how many times to recurse while formatting the
	object. This is useful for inspecting large complicated objects. Defaults to
	<code>2</code>. To make it recurse indefinitely pass <code>null</code>.</p>
	</li>
	<li><p><code>colors</code> - if <code>true</code>, then the output will be styled with ANSI color codes.
	Defaults to <code>false</code>. Colors are customizable, see below.</p>
	</li>
	<li><p><code>customInspect</code> - if <code>false</code>, then custom <code>inspect()</code> functions defined on the
	objects being inspected won't be called. Defaults to <code>true</code>.</p>
	</li>
	</ul>
	<p>Example of inspecting all properties of the <code>util</code> object:

	</p>
	<pre><code>var util = require('util');

	console.log(util.inspect(util, { showHidden: true, depth: null }));</code></pre>
	<h3>Customizing <code>util.inspect</code> colors<span><a class="mark" href="#util_customizing_util_inspect_colors" id="util_customizing_util_inspect_colors">#</a></span></h3>
	<p>Color output (if enabled) of <code>util.inspect</code> is customizable globally
	via <code>util.inspect.styles</code> and <code>util.inspect.colors</code> objects.

	</p>
	<p><code>util.inspect.styles</code> is a map assigning each style a color
	from <code>util.inspect.colors</code>.
	Highlighted styles and their default values are:
	<em> <code>number</code> (yellow)
	</em> <code>boolean</code> (yellow)
	<em> <code>string</code> (green)
	</em> <code>date</code> (magenta)
	<em> <code>regexp</code> (red)
	</em> <code>null</code> (bold)
	<em> <code>undefined</code> (grey)
	</em> <code>special</code> - only function at this time (cyan)
	* <code>name</code> (intentionally no styling)

	</p>
	<p>Predefined color codes are: <code>white</code>, <code>grey</code>, <code>black</code>, <code>blue</code>, <code>cyan</code>,
	<code>green</code>, <code>magenta</code>, <code>red</code> and <code>yellow</code>.
	There are also <code>bold</code>, <code>italic</code>, <code>underline</code> and <code>inverse</code> codes.

	</p>
	<p>Objects also may define their own <code>inspect(depth)</code> function which <code>util.inspect()</code>
	will invoke and use the result of when inspecting the object:

	</p>
	<pre><code>var util = require('util');

	var obj = { name: 'nate' };
	obj.inspect = function(depth) {
	return '{' + this.name + '}';
	};

	util.inspect(obj);
	// "{nate}"</code></pre>
	<h2>util.isArray(object)<span><a class="mark" href="#util_util_isarray_object" id="util_util_isarray_object">#</a></span></h2>
	<p>Returns <code>true</code> if the given "object" is an <code>Array</code>. <code>false</code> otherwise.

	</p>
	<pre><code>var util = require('util');

	util.isArray([])
	// true
	util.isArray(new Array)
	// true
	util.isArray({})
	// false</code></pre>
	<h2>util.isRegExp(object)<span><a class="mark" href="#util_util_isregexp_object" id="util_util_isregexp_object">#</a></span></h2>
	<p>Returns <code>true</code> if the given "object" is a <code>RegExp</code>. <code>false</code> otherwise.

	</p>
	<pre><code>var util = require('util');

	util.isRegExp(/some regexp/)
	// true
	util.isRegExp(new RegExp('another regexp'))
	// true
	util.isRegExp({})
	// false</code></pre>
	<h2>util.isDate(object)<span><a class="mark" href="#util_util_isdate_object" id="util_util_isdate_object">#</a></span></h2>
	<p>Returns <code>true</code> if the given "object" is a <code>Date</code>. <code>false</code> otherwise.

	</p>
	<pre><code>var util = require('util');

	util.isDate(new Date())
	// true
	util.isDate(Date())
	// false (without 'new' returns a String)
	util.isDate({})
	// false</code></pre>
	<h2>util.isError(object)<span><a class="mark" href="#util_util_iserror_object" id="util_util_iserror_object">#</a></span></h2>
	<p>Returns <code>true</code> if the given "object" is an <code>Error</code>. <code>false</code> otherwise.

	</p>
	<pre><code>var util = require('util');

	util.isError(new Error())
	// true
	util.isError(new TypeError())
	// true
	util.isError({ name: 'Error', message: 'an error occurred' })
	// false</code></pre>
	<h2>util.pump(readableStream, writableStream, [callback])<span><a class="mark" href="#util_util_pump_readablestream_writablestream_callback" id="util_util_pump_readablestream_writablestream_callback">#</a></span></h2>
	<pre class="api_stability_0">Stability: 0 - Deprecated: Use readableStream.pipe(writableStream)</pre><p>Read the data from <code>readableStream</code> and send it to the <code>writableStream</code>.
	When <code>writableStream.write(data)</code> returns <code>false</code> <code>readableStream</code> will be
	paused until the <code>drain</code> event occurs on the <code>writableStream</code>. <code>callback</code> gets
	an error as its only argument and is called when <code>writableStream</code> is closed or
	when an error occurs.


	</p>
	<h2>util.inherits(constructor, superConstructor)<span><a class="mark" href="#util_util_inherits_constructor_superconstructor" id="util_util_inherits_constructor_superconstructor">#</a></span></h2>
	<p>Inherit the prototype methods from one
	<a href="https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Object/constructor">constructor</a>
	into another. The prototype of <code>constructor</code> will be set to a new
	object created from <code>superConstructor</code>.

	</p>
	<p>As an additional convenience, <code>superConstructor</code> will be accessible
	through the <code>constructor.super_</code> property.

	</p>
	<pre><code>var util = require("util");
	var events = require("events");

	function MyStream() {
	events.EventEmitter.call(this);
	}

	util.inherits(MyStream, events.EventEmitter);

	MyStream.prototype.write = function(data) {
	this.emit("data", data);
	}

	var stream = new MyStream();

	console.log(stream instanceof events.EventEmitter); // true
	console.log(MyStream.super_ === events.EventEmitter); // true

	stream.on("data", function(data) {
	console.log('Received data: "' + data + '"');
	})
	stream.write("It works!"); // Received data: "It works!"</code></pre>

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