note 107246 deleted from language.oop5.magic by danbrown

Note Submitter: mightye at gmail dot com ---- osbertv at yahoo dot com: the problem is not that B contains an instance of A, the problem is that "$b->a()" looks for a method named "a" on $b, and when one is not found, it calls B's __invoke(). This is an order of operations thing, the compiler couldn't hope to know whether you meant to call B::a() or B::$a(). The previous one can be compile-time optimized while the latter one cannot (since there is no guarantee that B::$a is always callable). When there is a collision of intent like this, the compiler tends to give priority to the optimizable use case over the unoptimizable use case. You can either choose to proxy a call to $this->a; inside of B::__invoke() (probably with something like: return call_user_func_array($this->a, func_get_args()); ), or you can make an actual method B::a() for the same purpose (which would be faster). However, either way, it's probably not a great idea to be trying to use properties as though they were methods. The code this would produce can be very confusing to read. Creating B::a() solves this readability problem.