Mastering High Performance with Kotlin

Implicit delegation

Implicit delegation is a language-level feature. With implicit delegation, we use a special language construction or keyword to implement delegation instead of overriding methods explicitly. There are two types of implicit delegation:

• Unanticipated
• Anticipated

For unanticipated delegation, a delegate object can be replaced by another dynamically, whereas anticipated delegation doesn't let us change a delegate object during the delegating object's life cycle.

Kotlin supports only anticipated delegation as a language-level feature, but if Kotlin-supported unanticipated delegation, it could look as follows:

class CalculatorMachine(var delegate: Calculator): Calculator by delegateval calculator = CalculatorMachine(simpleCalculator) ...