basic_closure.swift

// Without params and return type
let closureFunc = {
  print("Printed from a closure")
}
closureFunc() // Printed from a closure

// With a parameter
let closureWithParams = { (name:String) in
  print("My name is \(name)")
}
closureWithParams("John") // My name is John

// With a return
let closureWithReturn = { () -> String in
  return "Hi mate"
}
print(closureWithReturn()) // Hi mate

// To use closure as a parameter
let imJohn = {  () -> String in
  return "John"
}
let printName = { (getName: () -> String) in
  print("I am \(getName())")
}
printName(imJohn) // I am John

// To use two parameters in a closure
let manify = {
  return "a man"
}
let genderify = { (_ name:String, gender: () -> String ) in
  print("\(name) is \(gender())")
}
genderify("John", manify) // John is a man

// Using a trailing clousre in a different syntax
genderify("Sansa", {
  return "a women"
}) // Sansa is a women

// Complex case
let detailify = { (adj: ()-> String) in
  genderify("John", {
    return "\(manify()) and \(adj())"
  })
}
detailify({
  return "short"
}) // John is a man and short