gistfile1.swift

// MyClass.swift

class MyClass {
  func doSomething() {
    refresh()
  }
}

//**
private func refresh() {
  println("I'm the global refresh function.")
}


// main.swift

// Oh dear, we didn't know that there was an internal private function called refresh...
extension MyClass {
  func refresh() {
    println("I'm an extension refresh")
  }
}

MyClass().doSomething()

// And our refresh() ** gets called. I wasn't expecting swizzling to happen quite so subltly.

// see also https://gist.github.com/rnapier/478465d1b15e95b98b42