There is a lot of overhead in using a framework, with the gain of fast development.
On Sat, May 2, 2009 at 10:34 PM, Kendall Bennett <[email protected]>wrote: > Ok, I have been going through the paces learning Zend Framework and the > pieces involved, and sometime it seems like design patterns are used when > they end up just creating lots of overhead, for zero gain. > > Consider the Zend_Registry class, and the registry design pattern it is > implementing. For starters, accessing methods in the registry class is not > exactly free. There is a lot of overhead involved in getting into the > registry class and finding the information needed, way more overhead than > just accessing a global variable. > > Now, I am sure we all agree that global variables are a bad thing, > especially global variables that are accessible everywhere. To me, that is > what the registry design pattern is intended to solve, but PHP does NOT > have > this problem. Global variables in PHP are only accessible from code running > in the global space, not from within functions or from within methods. At > least not unless you specifically declare a variable as Oglobal¹. So once > you are inside a function, or inside a class method, none of the globals in > the global space are actually in scope, so it is not possible to > accidentally change the globals or use them out of context (which is the > danger of globals in languages like C and C++). > > In all our PHP code we prefer to use the $GLOBALS super global to access > global variables, rather than using the global declaration, as it makes it > clear you are accessing a global variable. So we would use this: > > function set_global() > { > $GLOBALS['my_global'] = 'fun_stuff'; > } > > function use_global() > { > $use_global = $GLOBALS['my_global']; > } > > rather than this: > > function set_global() > { > global $my_global; > $my_global = 'fun_stuff'; > } > > function use_global() > { > global $my_global; > $use_global = $my_global; > } > > Now. In both of these cases, the global variables are NOT by default in the > scope of the function that uses them, and in the context of a framework > like > Zend Framework, nothing runs in the global space anyway, except the very > first index.php file that boostraps everything. > > So, according to the Registry design pattern modeled by Zend_Registry, we > should do this instead: > > function set_global() > { > $my_global = Zend_Registry::set('my_global','fun_stuff'); > } > > function use_global() > { > $use_global = Zend_Registry::get('my_global'); > } > > Now clearly this is not all that much different to my first example above > that uses the super global $GLOBALS. In fact, using the $GLOBALS variable > is > less typing, just as clear and more importantly, has ZERO overhead to using > it. Unlike the Zend_Registry::get() function that executes quite a lot of > code just to get a global variable. > > So after examining this some more, it seems to me both a waste of typing > and > waste of CPU resources to use the Zend_Registry class, when you can just as > easily reach for the $GLOBALS super global variable for the very few > instances where you do need access to global information. > > Regards, > > Kendall Bennett, CEO > A Main Hobbies > 424 Otterson Drive, Suite 160 > Chico, CA 95928 > 1-800-705-2215 (Toll-Free) > 1-530-894-0797 (Int'l & Local) > 1-530-894-9049 (Fax) > http://www.amainhobbies.com > >
