Swift, Kotlin, and Dart: A Tale of Shared Traits and Synergy

Swift, Kotlin, and Dart are modern programming languages designed with developer productivity, safety, and ease of use in mind. While each targets different ecosystems (Swift for Apple's platforms, Kotlin for Android and JVM, and Dart for Flutter), they share several commonalities. Here's an in-depth look at their similarities:

Modern and Clean Syntex

• All three languages emphasize clean, concise, and readable syntax to reduce boilerplate and improve code clarity.
• They adopt similar approaches to defining variables and functions, favouring simplicity and readability.

// Swift
let message = "Hello, Swift!"
print(message)        

// Kotlin
val message = "Hello, World!"
println(message)        

// Dart 
var message = "Hello, Dart!";
 print(message);        

Type-Safe with Type Inference

• All three languages support type inference, allowing developers to omit explicit type declarations when they are obvious.

• Swift, Kotlin and Dart are statically typed languages, meaning types are checked at compile time. This helps catch errors early in the development process.

let number =  10  // Swift infers it as Int

val number = 10 // Inferred as Int        

var number = 10;   // Dart infers it as int        

Null Safety

Swift, Kotlin, and Dart prioritize null safety to minimize null pointer exceptions. This feature encourages developers to handle potential null values explicitly.

• Swift uses Optional types (?) to indicate nullable values.
• Kotlin uses nullable types (?) and provides safe-call (?.) and Elvis (?:) operators.
• Dart has null safety, using ? for nullable types and requiring non-nullable types to be initialized.

// Swift
 var name: String?     // Optional 
 name = "Satendra" // Can be nil or assigned a value

// Kotlin
 var name: String?    // Optional 
 name = "Satendra" // Can be nil or assigned a value        

// Dart 
String? name;                         // Nullable 
 name = "Satendra";   // Can be null or assigned a value        

Object-Oriented and Protocol-Oriented Programming

• Each language supports object-oriented principles such as classes, inheritance, and polymorphism.
• Swift introduces protocol-oriented programming and Kotlin provides interfaces, which are similar to protocols in Swift, to support protocol-oriented programming (POP) while Dart has a similar concept through interfaces.

// Swift  
class Animal {  
    func makeSound() {  
        print("Animal sound")  
    }  
}  

class Dog: Animal {  
     func makeSound() {  
        print("Bark")  
    }  
}         

// Kotlin  
open class Animal {
    open fun makeSound() {
        println("Animal sound")
    }
}

class Dog : Animal() {
    override fun makeSound() {
        println("Bark")
    }
}        

// Dart  
class Animal {
  void makeSound() {
    print("Animal sound");
  }
}

class Dog extends Animal {
  @override
  void makeSound() {
    print("Bark");
  }
}        

Asynchronous Programming

All three languages support asynchronous programming using async and await for managing asynchronous operations.

// Swift  
func fetchData() async {  
    // Network call  
}  

// Call using async/await  
Task {  
    await fetchData()  
}         

// Kotlin
suspend fun fetchData(): String {
    return "Data from server"
}        

// Dart  
Future<void> fetchData() async {  
    // Network call  
}  

// Call using async/await  
void main() async {  
    await fetchData();  
}          

Enums with Associated Values

Swift and Dart languages support enums with associated values, allowing more expressive data structures.

In Kotlin, enum classes do not directly support associated values like Swift's enums. However, Kotlin provides a way to achieve similar functionality using sealed classes or by defining properties inside the enum class.

// Swift
enum Result {
    case success(data: String)
    case failure(error: String)
}        

// Dart
enum Result {
    success(String data),
    failure(String error),
}        

Functional Programming Features

Swift, Kotlin and Dart support functional programming concepts like first-class functions, higher-order functions, and closures(lambda expression).

// Swift
let numbers = [1, 2, 3, 4].map { $0 * 2 }        

// Kotlin
val numbers = listOf(1, 2, 3, 4).map { it * 2 }        

// Dart
var numbers = [1, 2, 3, 4].map((num) => num * 2).toList();        

Extension Methods

All three languages allow extending existing types with new methods.

// Swift
extension String {
    func reversedString() -> String {
        return String(self.reversed())
    }
}        

// Kotlin
fun String.reversedString(): String {
    return this.reversed()
}        

// Dart
extension StringExtensions on String {
    String reversedString() {
        return this.split('').reversed.join();
    }
}        

Memory Management

Both use modern memory management techniques:

• Swift: Uses Automatic Reference Counting (ARC).
• Kotlin: Uses Garbage Collection (GC) on the JVM.
• Dart: Uses a Garbage Collector (GC).

Interoperability

Both languages have strong interoperability:

• Swift interoperates with Objective-C.
• Kotlin: Works with Java.
• Dart interoperates with platform-specific code (Kotlin/Java for Android, Swift/Objective-C for iOS).

Platform-Specific Optimizations

While Swift is deeply integrated into Apple’s ecosystem, Kotlin is integrated into the Android ecosystem And Dart (with Flutter) provides similar seamless integration for cross-platform apps.

Conclusion

Swift, Kotlin and Dart share several design philosophies and language features that make them modern and developer-friendly. Understanding these similarities can be beneficial for developers transitioning between the two languages or working on cross-platform projects.