Framework to handle specializations
I have an application where I want to cut down on the amount of separate versions of code for each customization. One client gets one version another does not need the customization so I want to find a framework or build one such that a pre processor gets called when an event occurs on the page due to a click and if there is function for the event registered, that functional specialization gets executed and then control returns to the outer function. We never change the outer function. It returns and exits or returns and continues. Is there anything on the market to do this?