Re: Static Class Member References

Richard Quadling wrote: > On 11 July 2010 23:19, Daniel Kolbo <kolb0057@umn.edu> wrote: >> Hello PHPers, >> >> I'm having some trouble understanding some PHP behaviour. The following >> example script exhibits the behaviour which I cannot understand. >> [code] >> <?php >> >> class A >> { >> public static $a = 3; >> >> function __construct() >> { >> //self::$a = $this; //[i] >> self::$a =& $this; //[ii] >> } >> } >> >> class B extends A >> { >> function __construct() >> { >> parent::__construct(); >> } >> } >> >> class C { >> var $c; >> >> function __construct() >> { >> $this->c =& A::$a; >> } >> >> } >> >> >> $c = new C; >> $b = new B; >> $cee = new C; >> >> var_dump($c->c); // [i] prints object(B), but [ii] prints int 3 >> var_dump($cee->c); // [i] prints object(B), and [ii] prints object(B) >> >> ?> >> [/code] >> >> Why does $c->c print 'int 3' ? >> >> I'm nervous to use "self::$a = $this;" because I don't want to be >> copying the whole object. However, isn't $this just a reference to the >> object, so "self::$a = $this;" is just copying the reference and not the >> actual object, right? >> >> Thanks in advance > > > What do you think the value should be? > > A static property is bound to the class and not to an instance of the class. > > So, &A::$a is a reference to the static value. If you alter the value, > it will be altered for a subclasses of A and for any other reference > to it. > I think var_dump($c->c); would print object(B), but it's printing int 3. The reference is *not* being updated. I think this is a bug. What do you think? Thanks `