reuse of code, controller inside view

[eluser]Unknown[/eluser]
it is not exactly what i meant. Imagine that before

$this->load->view('head');

i have 40 lines of code how to "head" should look fo this category and i also want to reuse this code.
Also some categories does not contain "head". Entire layout depends on most-outer view, so it would be nice to include controllers inside views. But by "controller" i mean something like snippet or module.