Calling controllers from controllers

[eluser]wiredesignz[/eluser]
[quote author="Colin Williams" date="1239404496"]It's really a matter of how CI was designed. A Controller is just an instance of CodeIgniter class. So, to have other controllers available to call, you need multiple instances of the entire CodeIgniter class.
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FYI, Modular Extensions as of versions 5.2 and 4.3 use a single CI application instance and seperate controller instances for module controllers as needed.