cocoa - objective-c #import @class -

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• @class vs. #import 15 answers

i can't use of #import , @class

let's try make things clear simple classical example: employee case.

i have class employee, class manager , class department.

employee superclass of manager , contain object department ( should import department? in employee.h or employee.m , should use #import or @class ? )

department contains array of employees should should import class employee.h ( should use import or class? , where? )

i know theres better way solve problem, using databases or that's not point, want understand when , use #import , , when use @class 

i tried read similar post didn't understand how works...

using @class hint compiler mean use class , can used when referencing class in kind of declaration. not import header file , therefore compile little faster. useful avoid circular inclusions.

using #import import header file during compilation , needed when relying on behavior of class in question. how compiler knows properties, methods, etc can used safely.