Swift Tutorial - Tutorialspoint

Inside Sum Block:(100, 200)

Inside Diff Block: (200, 100)

Methods

New instance methods and type methods can be added further to the subclass with the
help of extensions.

extension Int {

func topics(summation: () -> ()) {

for _ in 0..<self {

summation()

}

}

}

4.topics({

println("Inside Extensions Block")

})

3.topics({

println("Inside Type Casting Block")

})

When we run the above program using playground, we get the following result:

Inside Extensions Block

Inside Extensions Block

Inside Extensions Block

Inside Extensions Block

Inside Type Casting Block

Inside Type Casting Block

Inside Type Casting Block

topics() function takes argument of type '(summation: () -> ())' to indicate the function
does not take any arguments and it won't return any values. To call that function multiple
number of times, for block is initialized and call to the method with topic() is initialized.