design pattern

-- HikaShop version -- : 2.4.0
-- Joomla version -- : 2.5.8
-- PHP version -- : 5.5.8

Hi i begin to learn php and because i find hks forum more supportive than joomla ....the best is study hks code rather than joomla. I read from developper that understand /detect design pattern ( gang of four) in php code help undertstand php code structure-interraction ; Does hikashop use some in they code ? Does uml diagram exist for joomla and hikashop ... Does it make sense to have documention about design pattern ?

• plugin architecture follows the Observer / publisher/subscriber design pattern uc .
• component architecture follows the MVC design pattern using JController, JModel and JView .
• module architecture follows the ? design pattern.
• JDatabase follow the Strategy Pattern ( before singleton )
• JFactory follows the Registry Pattern & Abstract Factory Pattern
• Template override follows the View/layout pattern
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