Practical Design Patterns in Swift

Introduction

• Explore the benefits of design patterns
• What you should know

• What’s a software design pattern?
• Applications of design patterns
• Limitations
• Creational, structural, and behavioral patterns

• Purpose, pros, and cons
• Read-only singletons
• Concurrency issues
• Making the singleton thread-safe
• Readers-writer lock

• Purpose: Cloning
• Copying value types
• Pitfalls of cloning reference types
• Cloning reference types

• Polymorphic instantiation
• Implementing the Factory Method

• Working with incompatible interfaces
• Classical Adapter
• Adapter using type extensions

• Enhancing a type without modifying it
• The object Decorator
• Decorator via Swift extensions

• Purpose: Simplify usage
• Consolidating complex functionality

• Sharing of common data
• Spaceships

• The surrogate
• Delayed initialization

• Request propagation
• Request processor

• Sequential access
• Custom queue implementation
• Adding for-in loop support to the queue

• Broadcasting
• Notifying observers

• Aim: Reduce complex conditional logic
• Coffee machine with nested conditionals
• Refactoring: Identifying the states
• Refactoring: Implementing the states

• Next steps