What is a integer property and what's the meaning of '\0A\0A'?
<p>I read this from the <a href="http://php.net/manual/en/language.types.array.php" rel="nofollow">PHP manual</a>:</p>

<blockquote>
  <p>If an object is converted to an array, the result is an array whose
  elements are the object's properties. The keys are the member variable
  names, with a few notable exceptions: <strong><em>integer properties are
  unaccessible</em></strong>; private variables have the class name prepended to the
  variable name; protected variables have a '*' prepended to the
  variable name. <strong><em>These prepended values have null bytes on either side.</em></strong>
  <em><strong>This can result in some unexpected behaviour:</em></strong> </p>

<pre><code>class A {
    private $A; // This will become '\0A\0A' }

class B extends A {
    private $A; // This will become '\0B\0A'
    public $AA; // This will become 'AA' }

var_dump((array) new B()); 
</code></pre>
  
  <p><em><strong>The above will appear to have two keys named 'AA', although one of</em></strong>
  <em><strong>them is actually named '\0A\0A'.</em></strong></p>
</blockquote>

<p>I don't quite understand the meaning of those parts with typeface like <strong><em>this</em></strong>.</p>

<p>What's a integer property?</p>

<p>What's the meaning of "These prepended values have null bytes on either side. This can result in some unexpected behaviour"? </p>

<p>and What's the meaning of "?The above will appear to have two keys named 'AA', although one of them is actually named '\0A\0A'"</p>
