🍧 Decorator Pattern

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The decorator pattern is used to extend or alter the functionality of objects at run- time by wrapping them in an object of a decorator class. This provides a flexible alternative to using inheritance to modify behaviour.

Github https://github.com/sergeyleschev/design-patterns

Example

protocol CostHaving {
    var cost: Double { get }
}
protocol IngredientsHaving {
    var ingredients: [String] { get }
}

typealias BeverageDataHaving = CostHaving & IngredientsHaving
struct SimpleCoffee: BeverageDataHaving {
    let cost: Double = 1.0
    let ingredients = ["Water", "Coffee"]
}

protocol BeverageHaving: BeverageDataHaving {
    var beverage: BeverageDataHaving { get }
}

struct Milk: BeverageHaving {
    let beverage: BeverageDataHaving
    var cost: Double {
        return beverage.cost + 0.5
    }
    var ingredients: [String] {
        return beverage.ingredients + ["Milk"]
    }
}

struct WhipCoffee: BeverageHaving {

    let beverage: BeverageDataHaving

    var cost: Double {
        return beverage.cost + 0.5
    }

    var ingredients: [String] {
        return beverage.ingredients + ["Whip"]
    }
}

Usage:

var someCoffee: BeverageDataHaving = SimpleCoffee()
print("Cost: \(someCoffee.cost); Ingredients: \(someCoffee.ingredients)")
someCoffee = Milk(beverage: someCoffee)
print("Cost: \(someCoffee.cost); Ingredients: \(someCoffee.ingredients)")
someCoffee = WhipCoffee(beverage: someCoffee)
print("Cost: \(someCoffee.cost); Ingredients: \(someCoffee.ingredients)")

Sources: Github

Structural
In software engineering, structural design patterns are design patterns that ease the design by identifying a simple way to realize relationships between entities.
Source: wikipedia.org

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🐝 Chain Of Responsibility
👫 Command Pattern
🎶 Interpreter Pattern
🍫 Iterator Pattern
💐 Mediator Pattern
💾 Memento Pattern
👓 Observer Pattern
🐉 State Pattern
💡 Strategy Pattern
📝 Template Method
🏃 Visitor Pattern
🌰 Abstract Factory
👷 Builder Pattern
🏭 Factory Method
🔂 Monostate Pattern
🃏 Prototype Pattern
💍 Singleton
🔌 Adapter Pattern
🌉 Bridge Pattern
🌿 Composite Pattern
🍧 Decorator Pattern
🎁 Facade Pattern
🍃 Flyweight Pattern
☔ Protection Proxy
🍬 Virtual Proxy

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Contacts
I have a clear focus on time-to-market and don't prioritize technical debt. And I took part in the Pre-Sale/RFX activity as a System Architect, assessment efforts for Mobile (iOS-Swift, Android-Kotlin), Frontend (React-TypeScript) and Backend (NodeJS-.NET-PHP-Kafka-SQL-NoSQL). And I also formed the work of Pre-Sale as a CTO from Opportunity to Proposal via knowledge transfer to Successful Delivery.

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