Explain async , awa...

Async and await are keywords used in Dart to handle asynchronous code. Here's how they work:

async

The async keyword is used to mark a function as asynchronous. It allows the function to use await and returns a Future by default[1][2].

When you call an async function, it immediately returns a Future object. The function's body continues executing in the background while the Future is returned[1][4].

await

The await keyword is used inside async functions to wait for a Future to complete before continuing execution[1][2][4]. It suspends the execution of the async function until the awaited Future completes[3].

When an await expression is evaluated, the asynchronous function is paused, and the control returns to the caller until the Future completes[5].

Execution flow

An async function runs synchronously until the first await keyword. All synchronous code before the first await executes immediately[5].

After the await, the function is paused until the awaited Future completes. Then, the function resumes execution[3][5].

Example

Future<String> fetchUserOrder() {
  // Imagine that this function is more complex and slow.
  retur...