A fairly dumb question...

[eluser]Hyra[/eluser]
The main difference, if not the only one, is that you use the double colon for static members, and the arrow for members


Static Member

Code:

class Foo
{
   public static $my_static = 'foo';

   public function staticValue() {
       return self::$my_static;
   }
}

class Bar extends Foo
{
   public function fooStatic() {
       return parent::$my_static;
   }
}


print Foo::$my_static . "\n";

$foo = new Foo();
print $foo->staticValue() . "\n";
print $foo->my_static . "\n";      // Undefined "Property" my_static

// $foo::my_static is not possible

print Bar::$my_static . "\n";
$bar = new Bar();
print $bar->fooStatic() . "\n";

Static method

Code:

class Foo {
   public static function aStaticMethod() {
       // ...
   }
}

Foo::aStaticMethod();

So .. :: can only be used for static (non-changing) methods/members