iOS - Make swift extension selectively visible -

in swift, how make extension visible few classes , not all?

i have added extension uiimage in file called uiimage+filters.swift. using extension in 2 classes in project photoimage , photosviewcontroller. want extension visible these 2 classes. how can achieve this?

that's not possible, access modifiers of classes/extensions behave consistent through units, separating privileges between outside modules , module are. means can declare class/extension accesible inside app/module , not accesible outsiders or visible everybody.

swift3 comes new access modifier, nothing restrict access partially inside module/app.