Swift - Protocol in swift [ swift programming language apple ios]

Protocol

“Classes, enumerations, and structs can all adopt protocols.”

protocol ExampleProtocol {

    var simpleDescription: String { get }

    mutating func adjust()

}

struct SimpleStructure: ExampleProtocol {

    var simpleDescription: String = "A simple structure"

    mutating func adjust() {

        simpleDescription += " (adjusted)"

    }

}

“ mutating keyword in the declaration of SimpleStructure to mark a method that modifies the structure.”