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                 <a href="debugger.json">View as JSON</a>
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           <div id="toc">
             <h2>Table of Contents</h2>
             <ul>
 <li><a href="#debugger_debugger">Debugger</a><ul>
 <li><a href="#debugger_watchers">Watchers</a></li>
 <li><a href="#debugger_commands_reference">Commands reference</a><ul>
 <li><a href="#debugger_stepping">Stepping</a></li>
 <li><a href="#debugger_breakpoints">Breakpoints</a></li>
 <li><a href="#debugger_info">Info</a></li>
 <li><a href="#debugger_execution_control">Execution control</a></li>
 <li><a href="#debugger_various">Various</a></li>
 </ul>
 </li>
 <li><a href="#debugger_advanced_usage">Advanced Usage</a></li>
 </ul>
 </li>
 </ul>

           </div>

           <div id="apicontent">
             <h1>Debugger<span><a class="mark" href="#debugger_debugger" id="debugger_debugger">#</a></span></h1>
 <pre class="api_stability_3">Stability: 3 - Stable</pre><!-- type=misc -->

 <p>V8 comes with an extensive debugger which is accessible out-of-process via a
 simple <a href="http://code.google.com/p/v8/wiki/DebuggerProtocol">TCP protocol</a>.
 Node has a built-in client for this debugger. To use this, start Node with the
 <code>debug</code> argument; a prompt will appear:

 </p>
 <pre><code>% node debug myscript.js
 &lt; debugger listening on port 5858
 connecting... ok
 break in /home/indutny/Code/git/indutny/myscript.js:1
   1 x = 5;
   2 setTimeout(function () {
   3   debugger;
 debug&gt;</code></pre>
 <p>Node&#39;s debugger client doesn&#39;t support the full range of commands, but
 simple step and inspection is possible. By putting the statement <code>debugger;</code>
 into the source code of your script, you will enable a breakpoint.

 </p>
 <p>For example, suppose <code>myscript.js</code> looked like this:

 </p>
 <pre><code>// myscript.js
 x = 5;
 setTimeout(function () {
   debugger;
   console.log(&quot;world&quot;);
 }, 1000);
 console.log(&quot;hello&quot;);</code></pre>
 <p>Then once the debugger is run, it will break on line 4.

 </p>
 <pre><code>% node debug myscript.js
 &lt; debugger listening on port 5858
 connecting... ok
 break in /home/indutny/Code/git/indutny/myscript.js:1
   1 x = 5;
   2 setTimeout(function () {
   3   debugger;
 debug&gt; cont
 &lt; hello
 break in /home/indutny/Code/git/indutny/myscript.js:3
   1 x = 5;
   2 setTimeout(function () {
   3   debugger;
   4   console.log(&quot;world&quot;);
   5 }, 1000);
 debug&gt; next
 break in /home/indutny/Code/git/indutny/myscript.js:4
   2 setTimeout(function () {
   3   debugger;
   4   console.log(&quot;world&quot;);
   5 }, 1000);
   6 console.log(&quot;hello&quot;);
 debug&gt; repl
 Press Ctrl + C to leave debug repl
 &gt; x
 5
 &gt; 2+2
 4
 debug&gt; next
 &lt; world
 break in /home/indutny/Code/git/indutny/myscript.js:5
   3   debugger;
   4   console.log(&quot;world&quot;);
   5 }, 1000);
   6 console.log(&quot;hello&quot;);
   7
 debug&gt; quit
 %</code></pre>
 <p>The <code>repl</code> command allows you to evaluate code remotely. The <code>next</code> command
 steps over to the next line. There are a few other commands available and more
 to come. Type <code>help</code> to see others.

 </p>
 <h2>Watchers<span><a class="mark" href="#debugger_watchers" id="debugger_watchers">#</a></span></h2>
 <p>You can watch expression and variable values while debugging your code.
 On every breakpoint each expression from the watchers list will be evaluated
 in the current context and displayed just before the breakpoint&#39;s source code
 listing.

 </p>
 <p>To start watching an expression, type <code>watch(&quot;my_expression&quot;)</code>. <code>watchers</code>
 prints the active watchers. To remove a watcher, type
 <code>unwatch(&quot;my_expression&quot;)</code>.

 </p>
 <h2>Commands reference<span><a class="mark" href="#debugger_commands_reference" id="debugger_commands_reference">#</a></span></h2>
 <h3>Stepping<span><a class="mark" href="#debugger_stepping" id="debugger_stepping">#</a></span></h3>
 <ul>
 <li><code>cont</code>, <code>c</code> - Continue execution</li>
 <li><code>next</code>, <code>n</code> - Step next</li>
 <li><code>step</code>, <code>s</code> - Step in</li>
 <li><code>out</code>, <code>o</code> - Step out</li>
 <li><code>pause</code> - Pause running code (like pause button in Developer Tools)</li>
 </ul>
 <h3>Breakpoints<span><a class="mark" href="#debugger_breakpoints" id="debugger_breakpoints">#</a></span></h3>
 <div class="signature"><ul>
 <li><code>setBreakpoint()</code>, <code>sb()</code> - Set breakpoint on current line</li>
 <li><code>setBreakpoint(line)</code>, <code>sb(line)</code> - Set breakpoint on specific line</li>
 <li><code>setBreakpoint(&#39;fn()&#39;)</code>, <code>sb(...)</code> - Set breakpoint on a first statement in
 functions body</li>
 <li><code>setBreakpoint(&#39;script.js&#39;, 1)</code>, <code>sb(...)</code> - Set breakpoint on first line of
 script.js</li>
 <li><code>clearBreakpoint</code>, <code>cb(...)</code> - Clear breakpoint</li>
 </div></ul>
 <p>It is also possible to set a breakpoint in a file (module) that
 isn&#39;t loaded yet:

 </p>
 <pre><code>% ./node debug test/fixtures/break-in-module/main.js
 &lt; debugger listening on port 5858
 connecting to port 5858... ok
 break in test/fixtures/break-in-module/main.js:1
   1 var mod = require(&#39;./mod.js&#39;);
   2 mod.hello();
   3 mod.hello();
 debug&gt; setBreakpoint(&#39;mod.js&#39;, 23)
 Warning: script &#39;mod.js&#39; was not loaded yet.
   1 var mod = require(&#39;./mod.js&#39;);
   2 mod.hello();
   3 mod.hello();
 debug&gt; c
 break in test/fixtures/break-in-module/mod.js:23
  21
  22 exports.hello = function() {
  23   return &#39;hello from module&#39;;
  24 };
  25
 debug&gt;</code></pre>
 <h3>Info<span><a class="mark" href="#debugger_info" id="debugger_info">#</a></span></h3>
 <div class="signature"><ul>
 <li><code>backtrace</code>, <code>bt</code> - Print backtrace of current execution frame</li>
 <li><code>list(5)</code> - List scripts source code with 5 line context (5 lines before and
 after)</li>
 <li><code>watch(expr)</code> - Add expression to watch list</li>
 <li><code>unwatch(expr)</code> - Remove expression from watch list</li>
 <li><code>watchers</code> - List all watchers and their values (automatically listed on each
 breakpoint)</li>
 <li><code>repl</code> - Open debugger&#39;s repl for evaluation in debugging script&#39;s context</li>
 </div></ul>
 <h3>Execution control<span><a class="mark" href="#debugger_execution_control" id="debugger_execution_control">#</a></span></h3>
 <div class="signature"><ul>
 <li><code>run</code> - Run script (automatically runs on debugger&#39;s start)</li>
 <li><code>restart</code> - Restart script</li>
 <li><code>kill</code> - Kill script</li>
 </div></ul>
 <h3>Various<span><a class="mark" href="#debugger_various" id="debugger_various">#</a></span></h3>
 <div class="signature"><ul>
 <li><code>scripts</code> - List all loaded scripts</li>
 <li><code>version</code> - Display v8&#39;s version</li>
 </div></ul>
 <h2>Advanced Usage<span><a class="mark" href="#debugger_advanced_usage" id="debugger_advanced_usage">#</a></span></h2>
 <p>The V8 debugger can be enabled and accessed either by starting Node with
 the <code>--debug</code> command-line flag or by signaling an existing Node process
 with <code>SIGUSR1</code>.

 </p>
 <p>Once a process has been set in debug mode with this it can be connected to
 with the node debugger. Either connect to the <code>pid</code> or the URI to the debugger.
 The syntax is:

 </p>
 <ul>
 <li><code>node debug -p &lt;pid&gt;</code> - Connects to the process via the <code>pid</code></li>
 <li>`node debug <URI> - Connects to the process via the URI such as localhost:5858</li>
 </ul>

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	<h1>Node.js v0.10.24 Manual & Documentation</h1>
	<div id="gtoc">
	<p>
	<a href="index.html" name="toc">Index</a> \|
	<a href="all.html">View on single page</a> \|
	<a href="debugger.json">View as JSON</a>
	</p>
	</div>
	<hr>
	</header>

	<div id="toc">
	<h2>Table of Contents</h2>
	<ul>
	<li><a href="#debugger_debugger">Debugger</a><ul>
	<li><a href="#debugger_watchers">Watchers</a></li>
	<li><a href="#debugger_commands_reference">Commands reference</a><ul>
	<li><a href="#debugger_stepping">Stepping</a></li>
	<li><a href="#debugger_breakpoints">Breakpoints</a></li>
	<li><a href="#debugger_info">Info</a></li>
	<li><a href="#debugger_execution_control">Execution control</a></li>
	<li><a href="#debugger_various">Various</a></li>
	</ul>
	</li>
	<li><a href="#debugger_advanced_usage">Advanced Usage</a></li>
	</ul>
	</li>
	</ul>

	</div>

	<div id="apicontent">
	<h1>Debugger<span><a class="mark" href="#debugger_debugger" id="debugger_debugger">#</a></span></h1>
	<pre class="api_stability_3">Stability: 3 - Stable</pre><!-- type=misc -->

	<p>V8 comes with an extensive debugger which is accessible out-of-process via a
	simple <a href="http://code.google.com/p/v8/wiki/DebuggerProtocol">TCP protocol</a>.
	Node has a built-in client for this debugger. To use this, start Node with the
	<code>debug</code> argument; a prompt will appear:

	</p>
	<pre><code>% node debug myscript.js
	< debugger listening on port 5858
	connecting... ok
	break in /home/indutny/Code/git/indutny/myscript.js:1
	1 x = 5;
	2 setTimeout(function () {
	3 debugger;
	debug></code></pre>
	<p>Node's debugger client doesn't support the full range of commands, but
	simple step and inspection is possible. By putting the statement <code>debugger;</code>
	into the source code of your script, you will enable a breakpoint.

	</p>
	<p>For example, suppose <code>myscript.js</code> looked like this:

	</p>
	<pre><code>// myscript.js
	x = 5;
	setTimeout(function () {
	debugger;
	console.log("world");
	}, 1000);
	console.log("hello");</code></pre>
	<p>Then once the debugger is run, it will break on line 4.

	</p>
	<pre><code>% node debug myscript.js
	< debugger listening on port 5858
	connecting... ok
	break in /home/indutny/Code/git/indutny/myscript.js:1
	1 x = 5;
	2 setTimeout(function () {
	3 debugger;
	debug> cont
	< hello
	break in /home/indutny/Code/git/indutny/myscript.js:3
	1 x = 5;
	2 setTimeout(function () {
	3 debugger;
	4 console.log("world");
	5 }, 1000);
	debug> next
	break in /home/indutny/Code/git/indutny/myscript.js:4
	2 setTimeout(function () {
	3 debugger;
	4 console.log("world");
	5 }, 1000);
	6 console.log("hello");
	debug> repl
	Press Ctrl + C to leave debug repl
	> x
	5
	> 2+2
	4
	debug> next
	< world
	break in /home/indutny/Code/git/indutny/myscript.js:5
	3 debugger;
	4 console.log("world");
	5 }, 1000);
	6 console.log("hello");
	7
	debug> quit
	%</code></pre>
	<p>The <code>repl</code> command allows you to evaluate code remotely. The <code>next</code> command
	steps over to the next line. There are a few other commands available and more
	to come. Type <code>help</code> to see others.

	</p>
	<h2>Watchers<span><a class="mark" href="#debugger_watchers" id="debugger_watchers">#</a></span></h2>
	<p>You can watch expression and variable values while debugging your code.
	On every breakpoint each expression from the watchers list will be evaluated
	in the current context and displayed just before the breakpoint's source code
	listing.

	</p>
	<p>To start watching an expression, type <code>watch("my_expression")</code>. <code>watchers</code>
	prints the active watchers. To remove a watcher, type
	<code>unwatch("my_expression")</code>.

	</p>
	<h2>Commands reference<span><a class="mark" href="#debugger_commands_reference" id="debugger_commands_reference">#</a></span></h2>
	<h3>Stepping<span><a class="mark" href="#debugger_stepping" id="debugger_stepping">#</a></span></h3>
	<ul>
	<li><code>cont</code>, <code>c</code> - Continue execution</li>
	<li><code>next</code>, <code>n</code> - Step next</li>
	<li><code>step</code>, <code>s</code> - Step in</li>
	<li><code>out</code>, <code>o</code> - Step out</li>
	<li><code>pause</code> - Pause running code (like pause button in Developer Tools)</li>
	</ul>
	<h3>Breakpoints<span><a class="mark" href="#debugger_breakpoints" id="debugger_breakpoints">#</a></span></h3>
	<div class="signature"><ul>
	<li><code>setBreakpoint()</code>, <code>sb()</code> - Set breakpoint on current line</li>
	<li><code>setBreakpoint(line)</code>, <code>sb(line)</code> - Set breakpoint on specific line</li>
	<li><code>setBreakpoint('fn()')</code>, <code>sb(...)</code> - Set breakpoint on a first statement in
	functions body</li>
	<li><code>setBreakpoint('script.js', 1)</code>, <code>sb(...)</code> - Set breakpoint on first line of
	script.js</li>
	<li><code>clearBreakpoint</code>, <code>cb(...)</code> - Clear breakpoint</li>
	</div></ul>
	<p>It is also possible to set a breakpoint in a file (module) that
	isn't loaded yet:

	</p>
	<pre><code>% ./node debug test/fixtures/break-in-module/main.js
	< debugger listening on port 5858
	connecting to port 5858... ok
	break in test/fixtures/break-in-module/main.js:1
	1 var mod = require('./mod.js');
	2 mod.hello();
	3 mod.hello();
	debug> setBreakpoint('mod.js', 23)
	Warning: script 'mod.js' was not loaded yet.
	1 var mod = require('./mod.js');
	2 mod.hello();
	3 mod.hello();
	debug> c
	break in test/fixtures/break-in-module/mod.js:23
	21
	22 exports.hello = function() {
	23 return 'hello from module';
	24 };
	25
	debug></code></pre>
	<h3>Info<span><a class="mark" href="#debugger_info" id="debugger_info">#</a></span></h3>
	<div class="signature"><ul>
	<li><code>backtrace</code>, <code>bt</code> - Print backtrace of current execution frame</li>
	<li><code>list(5)</code> - List scripts source code with 5 line context (5 lines before and
	after)</li>
	<li><code>watch(expr)</code> - Add expression to watch list</li>
	<li><code>unwatch(expr)</code> - Remove expression from watch list</li>
	<li><code>watchers</code> - List all watchers and their values (automatically listed on each
	breakpoint)</li>
	<li><code>repl</code> - Open debugger's repl for evaluation in debugging script's context</li>
	</div></ul>
	<h3>Execution control<span><a class="mark" href="#debugger_execution_control" id="debugger_execution_control">#</a></span></h3>
	<div class="signature"><ul>
	<li><code>run</code> - Run script (automatically runs on debugger's start)</li>
	<li><code>restart</code> - Restart script</li>
	<li><code>kill</code> - Kill script</li>
	</div></ul>
	<h3>Various<span><a class="mark" href="#debugger_various" id="debugger_various">#</a></span></h3>
	<div class="signature"><ul>
	<li><code>scripts</code> - List all loaded scripts</li>
	<li><code>version</code> - Display v8's version</li>
	</div></ul>
	<h2>Advanced Usage<span><a class="mark" href="#debugger_advanced_usage" id="debugger_advanced_usage">#</a></span></h2>
	<p>The V8 debugger can be enabled and accessed either by starting Node with
	the <code>--debug</code> command-line flag or by signaling an existing Node process
	with <code>SIGUSR1</code>.

	</p>
	<p>Once a process has been set in debug mode with this it can be connected to
	with the node debugger. Either connect to the <code>pid</code> or the URI to the debugger.
	The syntax is:

	</p>
	<ul>
	<li><code>node debug -p <pid></code> - Connects to the process via the <code>pid</code></li>
	<li>`node debug <URI> - Connects to the process via the URI such as localhost:5858</li>
	</ul>

	</div>
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