Asynchronous Programming Development Tutorials, Guides & Insights

Combine multiple coroutines to run concurrently:

import asyncio

async def task(name, duration):
    print(f"Task {name} started.")
    await asyncio.sleep(duration)
    print(f"Task {name} finished after {duration} seconds.")

async def main():
    await asyncio.gather(
        task("A", 2),
        task("B", 1),
        task("C", 3),
    )

asyncio.run(main())
# Output: Tasks A, B, and C execute concurrently.

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In this example, the count variable is private to the createCounter function. The only way to interact with it is through the increment and getCount methods, which form a closure around count.

    function setupEventHandlers() {
        const message = 'Button clicked!';

        document.getElementById('myButton').addEventListener('click', () => {
            alert(message);
        });
    }

    setupEventHandlers();

function fetchData(callback) {
    setTimeout(() => {
        callback("Data fetched");
    }, 2000);
}

console.log("Start");
fetchData((message) => {
    console.log(message);
});
console.log("End");

Start
End
Data fetched

The await keyword is used to pause the execution of an async function until the Future it is working on completes. This allows other tasks to run concurrently while waiting for the result.

async fn main() {
    let data = fetch_data("https://example.com").await.unwrap();
    println!("Fetched data: {}", data);
}