Go Composition Patterns

Composition patterns in Go are powerful design techniques that enable code reuse, flexibility, and maintainability through the combination of different types and behaviors. Unlike traditional inheritance-based object-oriented programming, Go emphasizes composition over inheritance, providing more flexible and maintainable code structures. Understanding composition patterns is crucial for writing idiomatic Go code and implementing sophisticated software architectures.

Understanding Composition Patterns in Go

What Are Composition Patterns?

Composition patterns in Go are design techniques that combine different types and behaviors to create more complex and flexible systems. These patterns provide:

Code reuse - Share functionality across different types
Flexibility - Easily modify and extend behavior
Maintainability - Clean, modular code structures
Testability - Easy to test individual components
Scalability - Build complex systems from simple components

Go's Composition Philosophy

Go's composition approach has several key characteristics:

Composition over Inheritance

Go encourages building complex types by combining simpler types rather than inheriting from them.

Interface-based Design

Interfaces provide contracts for composition and enable loose coupling.

Embedding and Delegation

Struct embedding enables automatic method promotion and field access.

Mixin Patterns

Reusable components can be embedded in multiple types.

Mixin Patterns and Traits

Understanding Mixins

Mixin Definition

Mixins are reusable components that provide specific functionality to multiple types.

Trait-like Behavior

Go's embedding enables trait-like behavior for code reuse.

package main

import "fmt"

func main() {
    // Mixin patterns and traits examples
    fmt.Println("Mixin patterns and traits examples:")
    
    // Timestamp mixin
    type Timestamp struct {
        CreatedAt string
        UpdatedAt string
    }
    
    func (t *Timestamp) SetCreatedAt(time string) {
        t.CreatedAt = time
    }
    
    func (t *Timestamp) SetUpdatedAt(time string) {
        t.UpdatedAt = time
    }
    
    func (t *Timestamp) GetCreatedAt() string {
        return t.CreatedAt
    }
    
    func (t *Timestamp) GetUpdatedAt() string {
        return t.UpdatedAt
    }
    
    // Logger mixin
    type Logger struct {
        LogLevel string
    }
    
    func (l *Logger) Log(message string) {
        fmt.Printf("[%s] %s\n", l.LogLevel, message)
    }
    
    func (l *Logger) SetLogLevel(level string) {
        l.LogLevel = level
    }
    
    func (l *Logger) GetLogLevel() string {
        return l.LogLevel
    }
    
    // Validator mixin
    type Validator struct {
        Rules []string
    }
    
    func (v *Validator) AddRule(rule string) {
        v.Rules = append(v.Rules, rule)
    }
    
    func (v *Validator) Validate(data interface{}) bool {
        fmt.Printf("Validating data with %d rules\n", len(v.Rules))
        return true // Simplified validation
    }
    
    func (v *Validator) GetRules() []string {
        return v.Rules
    }
    
    // Use mixins in different structs
    type User struct {
        ID        int
        Username  string
        Email     string
        Timestamp // Embedded mixin
        Logger    // Embedded mixin
        Validator // Embedded mixin
    }
    
    type Product struct {
        ID          int
        Name        string
        Price       float64
        Timestamp   // Embedded mixin
        Logger      // Embedded mixin
        Validator   // Embedded mixin
    }
    
    // Create user with mixins
    user := &User{
        ID:       1,
        Username: "alice",
        Email:    "[email protected]",
        Timestamp: Timestamp{},
        Logger:    Logger{LogLevel: "INFO"},
        Validator: Validator{},
    }
    
    // Use mixin methods
    user.SetCreatedAt("2023-12-07T10:00:00Z")
    user.SetUpdatedAt("2023-12-07T10:30:00Z")
    user.Log("User created successfully")
    user.AddRule("username must be unique")
    user.AddRule("email must be valid")
    user.Validate(user.Username)
    
    fmt.Printf("User: %s (%s)\n", user.Username, user.Email)
    fmt.Printf("Created: %s\n", user.GetCreatedAt())
    fmt.Printf("Updated: %s\n", user.GetUpdatedAt())
    fmt.Printf("Rules: %v\n", user.GetRules())
    // Output:
    // [INFO] User created successfully
    // Validating data with 2 rules
    // User: alice ([email protected])
    // Created: 2023-12-07T10:00:00Z
    // Updated: 2023-12-07T10:30:00Z
    // Rules: [username must be unique email must be valid]
    
    // Create product with mixins
    product := &Product{
        ID:        1,
        Name:      "Laptop",
        Price:     999.99,
        Timestamp: Timestamp{},
        Logger:    Logger{LogLevel: "DEBUG"},
        Validator: Validator{},
    }
    
    // Use mixin methods
    product.SetCreatedAt("2023-12-07T11:00:00Z")
    product.SetUpdatedAt("2023-12-07T11:15:00Z")
    product.Log("Product created successfully")
    product.AddRule("price must be positive")
    product.AddRule("name must not be empty")
    product.Validate(product.Name)
    
    fmt.Printf("Product: %s - $%.2f\n", product.Name, product.Price)
    fmt.Printf("Created: %s\n", product.GetCreatedAt())
    fmt.Printf("Updated: %s\n", product.GetUpdatedAt())
    fmt.Printf("Rules: %v\n", product.GetRules())
    // Output:
    // [DEBUG] Product created successfully
    // Validating data with 2 rules
    // Product: Laptop - $999.99
    // Created: 2023-12-07T11:00:00Z
    // Updated: 2023-12-07T11:15:00Z
    // Rules: [price must be positive name must not be empty]
}

Advanced Mixin Patterns

Conditional Mixins

Mixins that provide different behavior based on conditions.

Composable Mixins

Mixins that can be combined in different ways.

package main

import "fmt"

func main() {
    // Advanced mixin patterns examples
    fmt.Println("Advanced mixin patterns examples:")
    
    // Cache mixin
    type Cache struct {
        data map[string]interface{}
    }
    
    func (c *Cache) Get(key string) (interface{}, bool) {
        if c.data == nil {
            c.data = make(map[string]interface{})
        }
        value, exists := c.data[key]
        return value, exists
    }
    
    func (c *Cache) Set(key string, value interface{}) {
        if c.data == nil {
            c.data = make(map[string]interface{})
        }
        c.data[key] = value
    }
    
    func (c *Cache) Clear() {
        c.data = make(map[string]interface{})
    }
    
    // Metrics mixin
    type Metrics struct {
        counters map[string]int
    }
    
    func (m *Metrics) Increment(name string) {
        if m.counters == nil {
            m.counters = make(map[string]int)
        }
        m.counters[name]++
    }
    
    func (m *Metrics) GetCount(name string) int {
        if m.counters == nil {
            return 0
        }
        return m.counters[name]
    }
    
    func (m *Metrics) GetAllCounts() map[string]int {
        return m.counters
    }
    
    // Service mixin
    type Service struct {
        name    string
        running bool
    }
    
    func (s *Service) Start() {
        s.running = true
        fmt.Printf("Service %s started\n", s.name)
    }
    
    func (s *Service) Stop() {
        s.running = false
        fmt.Printf("Service %s stopped\n", s.name)
    }
    
    func (s *Service) IsRunning() bool {
        return s.running
    }
    
    // Composable service with mixins
    type UserService struct {
        Service // Embedded service
        Cache   // Embedded cache
        Metrics // Embedded metrics
    }
    
    func (us *UserService) GetUser(id string) (interface{}, bool) {
        us.Metrics.Increment("get_user_calls")
        
        // Try cache first
        if user, found := us.Cache.Get(id); found {
            us.Metrics.Increment("cache_hits")
            return user, true
        }
        
        // Simulate database lookup
        user := map[string]interface{}{
            "id":   id,
            "name": "User " + id,
        }
        
        us.Cache.Set(id, user)
        us.Metrics.Increment("cache_misses")
        return user, true
    }
    
    // Create user service
    userService := &UserService{
        Service: Service{name: "UserService"},
        Cache:   Cache{},
        Metrics: Metrics{},
    }
    
    // Start service
    userService.Start()
    
    // Use service
    user1, found := userService.GetUser("123")
    if found {
        fmt.Printf("Retrieved user: %v\n", user1)
    }
    // Output: Retrieved user: map[id:123 name:User 123]
    
    user2, found := userService.GetUser("123") // Should hit cache
    if found {
        fmt.Printf("Retrieved user (cached): %v\n", user2)
    }
    // Output: Retrieved user (cached): map[id:123 name:User 123]
    
    // Check metrics
    fmt.Printf("Get user calls: %d\n", userService.GetCount("get_user_calls"))
    fmt.Printf("Cache hits: %d\n", userService.GetCount("cache_hits"))
    fmt.Printf("Cache misses: %d\n", userService.GetCount("cache_misses"))
    // Output:
    // Get user calls: 2
    // Cache hits: 1
    // Cache misses: 1
    
    // Stop service
    userService.Stop()
}

Decorator Patterns

Understanding Decorator Patterns

Decorator Definition

Decorators wrap objects to add new functionality without modifying the original object.

Composition-based Decorators

Go's embedding enables clean decorator implementations.

package main

import "fmt"

func main() {
    // Decorator patterns examples
    fmt.Println("Decorator patterns examples:")
    
    // Define interface
    type Coffee interface {
        Cost() float64
        Description() string
    }
    
    // Base coffee
    type SimpleCoffee struct{}
    
    func (sc SimpleCoffee) Cost() float64 {
        return 2.0
    }
    
    func (sc SimpleCoffee) Description() string {
        return "Simple coffee"
    }
    
    // Milk decorator
    type MilkDecorator struct {
        Coffee // Embedded coffee
    }
    
    func (md MilkDecorator) Cost() float64 {
        return md.Coffee.Cost() + 0.5
    }
    
    func (md MilkDecorator) Description() string {
        return md.Coffee.Description() + ", with milk"
    }
    
    // Sugar decorator
    type SugarDecorator struct {
        Coffee // Embedded coffee
    }
    
    func (sd SugarDecorator) Cost() float64 {
        return sd.Coffee.Cost() + 0.3
    }
    
    func (sd SugarDecorator) Description() string {
        return sd.Coffee.Description() + ", with sugar"
    }
    
    // Vanilla decorator
    type VanillaDecorator struct {
        Coffee // Embedded coffee
    }
    
    func (vd VanillaDecorator) Cost() float64 {
        return vd.Coffee.Cost() + 0.7
    }
    
    func (vd VanillaDecorator) Description() string {
        return vd.Coffee.Description() + ", with vanilla"
    }
    
    // Create decorated coffees
    simpleCoffee := SimpleCoffee{}
    fmt.Printf("Simple coffee: %s - $%.2f\n", simpleCoffee.Description(), simpleCoffee.Cost())
    // Output: Simple coffee: Simple coffee - $2.00
    
    milkCoffee := MilkDecorator{Coffee: simpleCoffee}
    fmt.Printf("Milk coffee: %s - $%.2f\n", milkCoffee.Description(), milkCoffee.Cost())
    // Output: Milk coffee: Simple coffee, with milk - $2.50
    
    sugarMilkCoffee := SugarDecorator{Coffee: milkCoffee}
    fmt.Printf("Sugar milk coffee: %s - $%.2f\n", sugarMilkCoffee.Description(), sugarMilkCoffee.Cost())
    // Output: Sugar milk coffee: Simple coffee, with milk, with sugar - $2.80
    
    vanillaSugarMilkCoffee := VanillaDecorator{Coffee: sugarMilkCoffee}
    fmt.Printf("Vanilla sugar milk coffee: %s - $%.2f\n", vanillaSugarMilkCoffee.Description(), vanillaSugarMilkCoffee.Cost())
    // Output: Vanilla sugar milk coffee: Simple coffee, with milk, with sugar, with vanilla - $3.50
    
    // HTTP handler decorator example
    type Handler interface {
        Handle(request string) string
    }
    
    type BasicHandler struct{}
    
    func (bh BasicHandler) Handle(request string) string {
        return "Basic response for: " + request
    }
    
    type LoggingDecorator struct {
        Handler // Embedded handler
    }
    
    func (ld LoggingDecorator) Handle(request string) string {
        fmt.Printf("Logging: Handling request: %s\n", request)
        response := ld.Handler.Handle(request)
        fmt.Printf("Logging: Response: %s\n", response)
        return response
    }
    
    type AuthDecorator struct {
        Handler // Embedded handler
    }
    
    func (ad AuthDecorator) Handle(request string) string {
        fmt.Printf("Auth: Checking authentication for: %s\n", request)
        response := ad.Handler.Handle(request)
        fmt.Printf("Auth: Authentication successful\n")
        return response
    }
    
    // Create decorated handler
    handler := LoggingDecorator{
        Handler: AuthDecorator{
            Handler: BasicHandler{},
        },
    }
    
    // Use decorated handler
    response := handler.Handle("GET /users")
    fmt.Printf("Final response: %s\n", response)
    // Output:
    // Logging: Handling request: GET /users
    // Auth: Checking authentication for: GET /users
    // Auth: Authentication successful
    // Logging: Response: Basic response for: GET /users
    // Final response: Basic response for: GET /users
}

Strategy Patterns

Understanding Strategy Patterns

Strategy Definition

Strategy patterns define a family of algorithms and make them interchangeable.

Interface-based Strategies

Go's interfaces provide a clean way to implement strategy patterns.

package main

import "fmt"

func main() {
    // Strategy patterns examples
    fmt.Println("Strategy patterns examples:")
    
    // Define strategy interface
    type PaymentStrategy interface {
        Pay(amount float64) string
    }
    
    // Credit card strategy
    type CreditCardStrategy struct {
        CardNumber string
        CVV        string
    }
    
    func (ccs CreditCardStrategy) Pay(amount float64) string {
        return fmt.Sprintf("Paid $%.2f with credit card ending in %s", amount, ccs.CardNumber[len(ccs.CardNumber)-4:])
    }
    
    // PayPal strategy
    type PayPalStrategy struct {
        Email string
    }
    
    func (pps PayPalStrategy) Pay(amount float64) string {
        return fmt.Sprintf("Paid $%.2f with PayPal account %s", amount, pps.Email)
    }
    
    // Bank transfer strategy
    type BankTransferStrategy struct {
        AccountNumber string
        RoutingNumber string
    }
    
    func (bts BankTransferStrategy) Pay(amount float64) string {
        return fmt.Sprintf("Paid $%.2f with bank transfer from account %s", amount, bts.AccountNumber)
    }
    
    // Cryptocurrency strategy
    type CryptoStrategy struct {
        WalletAddress string
        Currency      string
    }
    
    func (cs CryptoStrategy) Pay(amount float64) string {
        return fmt.Sprintf("Paid $%.2f with %s to wallet %s", amount, cs.Currency, cs.WalletAddress[:8]+"...")
    }
    
    // Context that uses strategy
    type Order struct {
        ID      int
        Amount  float64
        Payment PaymentStrategy
    }
    
    func (o Order) ProcessPayment() string {
        return o.Payment.Pay(o.Amount)
    }
    
    // Create orders with different payment strategies
    orders := []Order{
        {
            ID:      1,
            Amount:  99.99,
            Payment: CreditCardStrategy{CardNumber: "1234567890123456", CVV: "123"},
        },
        {
            ID:      2,
            Amount:  149.99,
            Payment: PayPalStrategy{Email: "[email protected]"},
        },
        {
            ID:      3,
            Amount:  299.99,
            Payment: BankTransferStrategy{AccountNumber: "987654321", RoutingNumber: "123456789"},
        },
        {
            ID:      4,
            Amount:  199.99,
            Payment: CryptoStrategy{WalletAddress: "1A2B3C4D5E6F7G8H9I0J", Currency: "Bitcoin"},
        },
    }
    
    // Process payments with different strategies
    fmt.Println("Processing payments:")
    for _, order := range orders {
        fmt.Printf("Order %d: %s\n", order.ID, order.ProcessPayment())
    }
    // Output:
    // Processing payments:
    // Order 1: Paid $99.99 with credit card ending in 3456
    // Order 2: Paid $149.99 with PayPal account [email protected]
    // Order 3: Paid $299.99 with bank transfer from account 987654321
    // Order 4: Paid $199.99 with Bitcoin to wallet 1A2B3C4D...
    
    // Dynamic strategy selection
    type PaymentProcessor struct {
        strategies map[string]PaymentStrategy
    }
    
    func (pp *PaymentProcessor) RegisterStrategy(name string, strategy PaymentStrategy) {
        if pp.strategies == nil {
            pp.strategies = make(map[string]PaymentStrategy)
        }
        pp.strategies[name] = strategy
    }
    
    func (pp *PaymentProcessor) ProcessPayment(method string, amount float64) (string, error) {
        strategy, exists := pp.strategies[method]
        if !exists {
            return "", fmt.Errorf("payment method %s not supported", method)
        }
        return strategy.Pay(amount), nil
    }
    
    // Create payment processor
    processor := &PaymentProcessor{}
    
    // Register strategies
    processor.RegisterStrategy("credit_card", CreditCardStrategy{CardNumber: "1111222233334444", CVV: "456"})
    processor.RegisterStrategy("paypal", PayPalStrategy{Email: "[email protected]"})
    processor.RegisterStrategy("crypto", CryptoStrategy{WalletAddress: "9Z8Y7X6W5V4U3T2S1R0Q", Currency: "Ethereum"})
    
    // Process payments dynamically
    fmt.Println("\nDynamic payment processing:")
    methods := []string{"credit_card", "paypal", "crypto"}
    for _, method := range methods {
        result, err := processor.ProcessPayment(method, 50.0)
        if err != nil {
            fmt.Printf("Error: %v\n", err)
        } else {
            fmt.Printf("Method %s: %s\n", method, result)
        }
    }
    // Output:
    // Dynamic payment processing:
    // Method credit_card: Paid $50.00 with credit card ending in 4444
    // Method paypal: Paid $50.00 with PayPal account [email protected]
    // Method crypto: Paid $50.00 with Ethereum to wallet 9Z8Y7X6W...
}

Factory Patterns

Understanding Factory Patterns

Factory Definition

Factory patterns create objects without specifying their exact class.

Interface-based Factories

Go's interfaces provide a clean way to implement factory patterns.

package main

import "fmt"

func main() {
    // Factory patterns examples
    fmt.Println("Factory patterns examples:")
    
    // Define product interface
    type Animal interface {
        MakeSound() string
        Move() string
    }
    
    // Define factory interface
    type AnimalFactory interface {
        CreateAnimal() Animal
    }
    
    // Concrete products
    type Dog struct {
        Name  string
        Breed string
    }
    
    func (d Dog) MakeSound() string {
        return "Woof!"
    }
    
    func (d Dog) Move() string {
        return "Running on four legs"
    }
    
    type Cat struct {
        Name  string
        Breed string
    }
    
    func (c Cat) MakeSound() string {
        return "Meow!"
    }
    
    func (c Cat) Move() string {
        return "Walking gracefully"
    }
    
    type Bird struct {
        Name  string
        Species string
    }
    
    func (b Bird) MakeSound() string {
        return "Tweet!"
    }
    
    func (b Bird) Move() string {
        return "Flying through the air"
    }
    
    // Concrete factories
    type DogFactory struct{}
    
    func (df DogFactory) CreateAnimal() Animal {
        return Dog{Name: "Generic Dog", Breed: "Mixed"}
    }
    
    type CatFactory struct{}
    
    func (cf CatFactory) CreateAnimal() Animal {
        return Cat{Name: "Generic Cat", Breed: "Mixed"}
    }
    
    type BirdFactory struct{}
    
    func (bf BirdFactory) CreateAnimal() Animal {
        return Bird{Name: "Generic Bird", Species: "Mixed"}
    }
    
    // Use factory pattern
    factories := []AnimalFactory{
        DogFactory{},
        CatFactory{},
        BirdFactory{},
    }
    
    fmt.Println("Creating animals with factories:")
    for i, factory := range factories {
        animal := factory.CreateAnimal()
        fmt.Printf("Animal %d: %s - %s\n", i+1, animal.MakeSound(), animal.Move())
    }
    // Output:
    // Creating animals with factories:
    // Animal 1: Woof! - Running on four legs
    // Animal 2: Meow! - Walking gracefully
    // Animal 3: Tweet! - Flying through the air
    
    // Parameterized factory
    type ParameterizedAnimalFactory struct{}
    
    func (paf ParameterizedAnimalFactory) CreateAnimal(animalType string) (Animal, error) {
        switch animalType {
        case "dog":
            return Dog{Name: "Buddy", Breed: "Golden Retriever"}, nil
        case "cat":
            return Cat{Name: "Whiskers", Breed: "Persian"}, nil
        case "bird":
            return Bird{Name: "Tweety", Species: "Canary"}, nil
        default:
            return nil, fmt.Errorf("unknown animal type: %s", animalType)
        }
    }
    
    // Use parameterized factory
    paramFactory := ParameterizedAnimalFactory{}
    animalTypes := []string{"dog", "cat", "bird", "fish"}
    
    fmt.Println("\nCreating animals with parameterized factory:")
    for _, animalType := range animalTypes {
        animal, err := paramFactory.CreateAnimal(animalType)
        if err != nil {
            fmt.Printf("Error creating %s: %v\n", animalType, err)
        } else {
            fmt.Printf("%s: %s - %s\n", animalType, animal.MakeSound(), animal.Move())
        }
    }
    // Output:
    // Creating animals with parameterized factory:
    // dog: Woof! - Running on four legs
    // cat: Meow! - Walking gracefully
    // bird: Tweet! - Flying through the air
    // Error creating fish: unknown animal type: fish
    
    // Abstract factory pattern
    type Vehicle interface {
        Start() string
        Stop() string
    }
    
    type Car struct {
        Model string
    }
    
    func (c Car) Start() string {
        return fmt.Sprintf("Starting %s car", c.Model)
    }
    
    func (c Car) Stop() string {
        return fmt.Sprintf("Stopping %s car", c.Model)
    }
    
    type Motorcycle struct {
        Model string
    }
    
    func (m Motorcycle) Start() string {
        return fmt.Sprintf("Starting %s motorcycle", m.Model)
    }
    
    func (m Motorcycle) Stop() string {
        return fmt.Sprintf("Stopping %s motorcycle", m.Model)
    }
    
    type VehicleFactory interface {
        CreateCar() Vehicle
        CreateMotorcycle() Vehicle
    }
    
    type LuxuryVehicleFactory struct{}
    
    func (lvf LuxuryVehicleFactory) CreateCar() Vehicle {
        return Car{Model: "BMW X5"}
    }
    
    func (lvf LuxuryVehicleFactory) CreateMotorcycle() Vehicle {
        return Motorcycle{Model: "Harley Davidson"}
    }
    
    type EconomyVehicleFactory struct{}
    
    func (evf EconomyVehicleFactory) CreateCar() Vehicle {
        return Car{Model: "Toyota Corolla"}
    }
    
    func (evf EconomyVehicleFactory) CreateMotorcycle() Vehicle {
        return Motorcycle{Model: "Honda CBR"}
    }
    
    // Use abstract factory
    factories2 := []VehicleFactory{
        LuxuryVehicleFactory{},
        EconomyVehicleFactory{},
    }
    
    fmt.Println("\nCreating vehicles with abstract factory:")
    for i, factory := range factories2 {
        car := factory.CreateCar()
        motorcycle := factory.CreateMotorcycle()
        fmt.Printf("Factory %d:\n", i+1)
        fmt.Printf("  Car: %s\n", car.Start())
        fmt.Printf("  Motorcycle: %s\n", motorcycle.Start())
    }
    // Output:
    // Creating vehicles with abstract factory:
    // Factory 1:
    //   Car: Starting BMW X5 car
    //   Motorcycle: Starting Harley Davidson motorcycle
    // Factory 2:
    //   Car: Starting Toyota Corolla car
    //   Motorcycle: Starting Honda CBR motorcycle
}

What You've Learned

Congratulations! You now have a comprehensive understanding of Go's composition patterns:

Mixin Patterns and Traits

Understanding mixin patterns and their benefits
Implementing reusable components through embedding
Creating trait-like behavior in Go
Building composable and flexible systems

Decorator Patterns

Understanding decorator patterns and their use cases
Implementing decorators using embedding
Creating flexible and extensible object hierarchies
Building clean and maintainable decorator chains

Strategy Patterns

Understanding strategy patterns and polymorphism
Implementing interchangeable algorithms
Creating flexible and configurable systems
Building dynamic strategy selection mechanisms

Factory Patterns

Understanding factory patterns and object creation
Implementing different types of factories
Creating flexible object creation systems
Building parameterized and abstract factories

Key Concepts

Composition over inheritance - Building complex types from simpler ones
Mixin patterns - Reusable components through embedding
Decorator patterns - Adding functionality without modification
Strategy patterns - Interchangeable algorithms
Factory patterns - Flexible object creation

Next Steps

You now have a solid foundation in Go's composition patterns. In the next section, we'll explore advanced OOP patterns, which combine all the concepts we've learned to create sophisticated software architectures.

Understanding composition patterns is crucial for building maintainable, flexible, and scalable applications. These concepts form the foundation for all the more advanced programming techniques we'll cover in the coming chapters.

Ready to learn about advanced OOP patterns? Let's explore sophisticated design patterns and learn how to build complex, maintainable systems!

Understanding Composition Patterns in Go​

What Are Composition Patterns?​

Go's Composition Philosophy​

Composition over Inheritance​

Interface-based Design​

Embedding and Delegation​

Mixin Patterns​

Mixin Patterns and Traits​

Understanding Mixins​

Mixin Definition​

Trait-like Behavior​

Advanced Mixin Patterns​

Conditional Mixins​

Composable Mixins​

Decorator Patterns​

Understanding Decorator Patterns​

Decorator Definition​

Composition-based Decorators​

Strategy Patterns​

Understanding Strategy Patterns​

Strategy Definition​

Interface-based Strategies​

Factory Patterns​

Understanding Factory Patterns​

Factory Definition​

Interface-based Factories​

What You've Learned​

Mixin Patterns and Traits​

Decorator Patterns​

Strategy Patterns​

Factory Patterns​

Key Concepts​

Next Steps​

Understanding Composition Patterns in Go

What Are Composition Patterns?

Go's Composition Philosophy

Composition over Inheritance

Interface-based Design

Embedding and Delegation

Mixin Patterns

Mixin Patterns and Traits

Understanding Mixins

Mixin Definition

Trait-like Behavior

Advanced Mixin Patterns

Conditional Mixins

Composable Mixins

Decorator Patterns

Understanding Decorator Patterns

Decorator Definition

Composition-based Decorators

Strategy Patterns

Understanding Strategy Patterns

Strategy Definition

Interface-based Strategies

Factory Patterns

Understanding Factory Patterns

Factory Definition

Interface-based Factories

What You've Learned

Mixin Patterns and Traits

Decorator Patterns

Strategy Patterns

Factory Patterns

Key Concepts

Next Steps