SWIFT

declare function in swift

func greet(person: String) -> String {
    let greeting = "Hello, " + person + "!"
    return greeting
}

Swift Function Declaration

func functionName(parameters)-> returnType {
  // function body 
}

Swift Function

// declare a function
func greet() {
  print("Hello World!")
}

// call the function
greet()

print("Outside function")