This README provides a simple explanation of Swift protocols and delegates using a code example. In this example, we'll explore how to define protocols, implement them using classes and structs, and use delegates to delegate responsibilities.

• What are Protocols?
• What are Delegates?
• Understanding the Code
• How to Use the Code

Protocols in Swift define a blueprint for methods, properties, and other requirements that a conforming class or struct must implement. Protocols are a way to define a set of behaviors without specifying how those behaviors should be implemented. They enable you to achieve polymorphism and create more flexible and reusable code.

In the code provided, we have defined a protocol named AdvancedLifeSupport:

protocol AdvancedLifeSupport {
    func performCPR()
}

This protocol declares that any conforming type must implement a method called performCPR().

Delegates in Swift are a design pattern that allows one object to delegate or hand off tasks to another object. Delegates are commonly used to define a contract between two objects, where one object (the delegate) agrees to perform certain tasks on behalf of another object. This helps in achieving separation of concerns and modularity in your code.

In the code, we have an EmergencyCallHandler class that has a delegate property of type AdvancedLifeSupport. This means that the EmergencyCallHandler can delegate the task of performing CPR to another object that conforms to the AdvancedLifeSupport protocol.

Let's dive into the provided code to understand how protocols and delegates are used:

• We define the AdvancedLifeSupport protocol with a single method requirement: func performCPR().

• The EmergencyCallHandler class has a delegate property of type AdvancedLifeSupport, which can be set to any object that conforms to the protocol.

• We create two classes, Paramedic and Doctor, both of which conform to the AdvancedLifeSupport protocol. These classes implement the performCPR() method differently, simulating how different types of medical professionals would perform CPR.

• The Surgeon class is a subclass of Doctor and overrides the performCPR() method to add a unique behavior.

• Instances of Paramedic, Doctor, and Surgeon are initialized and associated with an EmergencyCallHandler instance, effectively becoming the delegate for that handler.

1. Create an EmergencyCallHandler instance:

   let emergencyCallHandler = EmergencyCallHandler()

2. Initialize a medical professional as the delegate (e.g., Paramedic or Doctor):

   let paramedic = Paramedic(handler: emergencyCallHandler)
   // or
   let doctor = Doctor(handler: emergencyCallHandler)

3. Assess the situation:

   emergencyCallHandler.assessSituation()

4. Trigger a medical emergency:

   emergencyCallHandler.medicalEmergency()

5. Observe the different behaviors of the delegate object when performing CPR based on the type of medical professional associated with the EmergencyCallHandler.

By following these steps, you can see how Swift protocols and delegates enable you to delegate responsibilities and achieve flexibility in your code, allowing different objects to respond to tasks in unique ways.

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