What"s the difference between async and async* in Dart?

📝 Title: Asynchronous 101: Unraveling the Mysteries of "async" and "async" in Dart*

📝 Introduction: Hey there, tech-savvy flutter enthusiasts! 🎈 Are you puzzled by the keywords "async" and "async*" in Dart? Don't worry, you're not alone! 🤔 In this blog post, we'll dive into the differences between these two keywords, unraveling their mysteries and providing easy solutions to common issues. So, grab your code editor and let's get started! 💻

📝 Section 1: Defining the Basics Before we jump into the differences, let's understand the fundamentals. Dart introduced the "async" keyword to handle asynchronous functions, which allow tasks to run concurrently without blocking the execution. 🏃‍♂️ Asynchronous functions are denoted by the "async" keyword in their function signature.

📜 Example:

Future<void> fetchUserData() async {
  // Simulating network request delay
  await Future.delayed(Duration(seconds: 2));
  print("User data fetched!");
}

📝 Section 2: The Power of "async" (Stream-based Asynchronous Programming)* Now, imagine you need to handle a continuous stream of data asynchronously. This is where the "async*" keyword, also known as a "stream," comes to your rescue! 🌊 Unlike regular asynchronous functions that return a single value, async* functions produce a stream of values over time. That's like having a constant flow of information without waiting for an endpoint.

📜 Example:

Stream<int> countNumbers() async* {
  for (int i = 1; i <= 5; i++) {
    await Future.delayed(Duration(seconds: 1));
    yield i;
  }
}

📝 Section 3: Key Differences Explained While both "async" and "async*" are used for handling asynchronous functionality, they have some crucial differences:

1. Return Type: "async" functions typically have a return type of Future<T>, where T represents the actual return type. Conversely, "async*" functions return a Stream<T>.

2. Data Flow: "async" functions execute a series of tasks concurrently and eventually return a single result. On the other hand, "async*" functions emit a stream of values over time, allowing for continuous data flow.

📝 Section 4: When to Use Each? To put it simply, use "async" when you have a function that performs a single asynchronous task and returns a future. On the flip side, utilize "async*" when you're dealing with streams and want to produce a continuous flow of data. 🌊

📝 Conclusion: Congratulations, flutter enthusiasts! You're now equipped with the knowledge to distinguish between the "async" and "async*" keywords in Dart. Remember, "async" manages individual asynchronous tasks, while "async*" (streams) handles continuous data flow. Whether you're fetching data or processing streams, Dart has got you covered! 🚀 So, go ahead, experiment with both keywords, and level up your asynchronous programming skills!

📝 Call-to-Action: Have you ever faced any hiccups with asynchronous programming in Dart? Share your experiences, tips, or questions in the comments below! Let's engage in a lively discussion and help each other conquer the world of asynchronous programming! 🌟💬