Apr 09: JavaScript Promises

Learning Objectives

After today’s class, you should be able to:

• Describe how Promises help manage asynchronous operations.
• Create a Promise to run a long-running function asynchronously.
• Explain how to use the keywords async and await in JavaScript.

Lesson Outline

Lecture [20 min]

• Chapter 10: Slides 31–36
  • Promise – MDN Reference
  • How async and await work
• PromisesPrimes.pdf: courtesy of Dr. Kirkpatrick

Example [10 min]

• prime.html
• prime.js

Activity [45 min]

• Project claims (3 min per team)
• Play Fetch: Parts 1–2 last tie, Part 3 today
  • Note: Don’t worry about GitHub Classroom
  • Clone play-fetch or click “Use this template”

Before Tuesday

1. Finish the reading from Prep 10.
2. Submit Lab 9 on Gradescope. ← Due Mon at 11:59pm
3. Make progress on Project 2 in your teamXX repository.