Implementing a Singleton Class in Swift

The Singleton design pattern guarantees that only on object of a class will exist in a system.

// Creating Singleton
// Only one instance of this class can be created
class CloudCodeExecutor {

    // Declare class instance property
    static let sharedInstance = CloudCodeExecutor()
   
    // Declare an initializer 
    // Because this class is singleton only one instance of this class can be created
    init() {
        print("CloudCodeExecutor has been initialized")
    }

    // Add a function
    func processCloudCodeOperation() {
        print("Started processing cloud code operation")

        // Your other code here
    }
}


// Call function of Singleton class
CloudCodeExecutor.sharedInstance.processCloudCodeOperation()

// Call cloud code operation function again
CloudCodeExecutor.sharedInstance.processCloudCodeOperation()

// And again to see that class initializer was called only once
CloudCodeExecutor.sharedInstance.processCloudCodeOperation()

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