``++$this++`` refers to the current class instance. But static methods can be accessed without instantiating the class, and ``++$this++`` is not available to them. Using ``++$this++`` in a static context will result in a fatal error at runtime.


== Noncompliant Code Example

----
class Clazz {
  $name=NULL;  // instance variable

  public static function foo(){
    if ($this->name != NULL) {
      // ...
    }
  }
}
----


== Compliant Solution

----
class Clazz {
  $name=NULL;  // instance variable

  public static function foo($nameParam){
    if ($nameParam != NULL) {
      // ...
    }
  }
}
----