How can I execute a block of code exactly once in PHP?
<p>I have one main.php file with a class definition. Other php files use this main.php file </p>

<pre><code>//main.php

&lt;?php

class A{


}

//I want to execute the following statements exactly once    

$a = new A();
/*
Some code 
*/


?&gt;
</code></pre>

<p>I use main.php in other php files like</p>

<pre><code>//php1.php
&lt;?php
require_once("main.php");

$b = new A();

/* 
Some code
*/

?&gt;

//php2.php
&lt;?php
require_once("main.php");

$b = new A();

/* 
Some code
*/

?&gt;
</code></pre>

<p>Is there any statement in PHP like execute_once()?
How do I solve this?</p>
