Private func in swift are hidden from the ObjC runtime

gistfile1.txt

import Foundation

class Testing : NSObject
{
    private func privateWork() {
    }
    
    internal func internalWork(){
    }
    
    func check(){
        self.respondsToSelector(Selector("privateWork"))    //false
        self.respondsToSelector(Selector("internalWork"))   //true
    }
}

let t = Testing()
t.check()

@iotize in runtime all obj-c selectors are "public".

@casademora: could it be that Swift simply inlined that func, noticed it's never used anywhere and therefore created no selector for it? So some more complex private function would show up in respondsToSelector?

@oleganza: I think Swift reserves the right to inline the private func. Much like the old JVM, it reserves the right to do lots of optimizations by enforcing rules.

@objc private func privateWork() - Now you get true//true, because it had to make a dynamically dispatched version which performSelector can see... just something to keep in mind.