Swift Tutorial - Tutorialspoint

length = breadth * 10

}

init(frombre bre: Double) {

length = bre * 30

}

init(_ area: Double) {

length = area

}

}

let rectarea = Rectangle(180.0)

println("area is: \(rectarea.length)")

let rearea = Rectangle(370.0)

println("area is: \(rearea.length)")

let recarea = Rectangle(110.0)

println("area is: \(recarea.length)")

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

area is: 180.0

area is: 370.0

area is: 110.0

Optional Property Types

When the stored property at some instance does not return any value that property is
declared with an 'optional' type indicating that 'no value' is returned for that particular
type. When the stored property is declared as 'optional' it automatically initializes the value
to be 'nil' during initialization itself.

struct Rectangle {

var length: Double?

init(frombreadth breadth: Double) {