Swiftly

Swift 5.1 references for busy coders

Booleans

A boolean (Bool) is a type that stores a true or false value:

let lightIsOn = true

Mutating

A mutable Bool’s value can be changed:

var lightIsOn = true
lightIsOn = false
print(lightIsOn) // false

Toggling

A convenient way to change a Bool’s value is with the toggle method:

var lightIsOn = true
lightIsOn.toggle()
print(lightIsOn) // false
lightIsOn.toggle()
print(lightIsOn) // true