Description
bool 
interface_exists ( string interface_name [, bool autoload] )
     This function returns TRUE if the interface given by
     interface_name has been defined,
     FALSE otherwise.
    
     
| Example 1. interface_exists() example | 
<?php// Check the interface exists before trying to use it
 if (interface_exists('MyInterface')) {
 class MyClass implements MyInterface
 {
 // Methods
 }
 }
 
 ?>
 | 
 | 
    
     interface_exists() will attempt to call __autoload by
     default, if you don't want interface_exists() to 
     call __autoload, you can set the parameter autoload
     to FALSE.
    
     See also class_exists().