What are creational design patterns?

Creational design patterns are templates that abstract the instantiation process, making the system independent of how and when objects are created.

Main creational patterns:

• Abstract Factory: Provides an interface for creating families of related or dependent objects without specifying their concrete classes.
• Builder: Separates the construction of a complex object from its representation so that the same construction process can create different representations.
• Factory Method: Defines an interface for creating an object but allows subclasses to decide which class to instantiate. The factory method lets a class delegate instantiation to subclasses.
• Prototype: Specifies the kinds of objects to create using a prototypical instance and creates new objects by copying this prototype.
• Singleton: Ensures that a class has only one instance and provides a global point of access to it.

Examples of usage:

• Abstract Factory can be used to create UI element sets for different operating systems (e.g., iOS and Android).
• Builder is useful when creating complex objects with many configuration options, such as URLRequest or network configuration.
• Factory Method is often used in frameworks to create views or controllers based on their string identifiers.
• Prototype allows efficient creation of new objects based on existing ones, such as cloning instances.
• Singleton is used for managers like URLSession.shared or UserDefaults.standard.

These patterns increase flexibility, reusability, and testability of code, hiding the details of object creation.