ios - Iterate through an NSArray of different classes that implement the same protocol with a for in loop -

i have method in instantiate array of objects derived same protocol. know if can iterate through array , execute common protocol method.

pseudocode

nsarray *implementations = @[/*impl1, impl2, impl3 instantiated here*/]   (__________ * impl in implementations){     [impl protocolmethod] } 

my issue don't know how define type of object in blank in for-in loop because different classes. closest can think of "id" doesn't seem valid type because "pointer non-const type no explicit ownership."

could this:

for (nsobject<myprotocol>* impl in implementations)     [impl protocolmethod] 

or even

for (id<myprotocol> impl in implementations)     [impl protocolmethod] 

i use first form it's bit more compile-time safe.