memento pattern

What is a Memento Pattern? The Memento Pattern helps return an object to one of its previous states; for instance, if the user requests an “undo” operation. Source What problems does it solve? The Memento Pattern helps solve following problems: Undo/Redo Functionality: Memento allows you to capture an object’s state at a specific point in time and store it externally. This enables you to implement undo/redo functionality by restoring the object to its previous state....