promises-exercises

Set of exercises in using JS promises for handling asynchronous operations.

Setup

1. Fork this repository.
2. Run npm install to download the Node modules.

Using

For these exercises, there are a few folders, each corresponding to a step in the lesson. Each of them has a README.md, a test.js, and an answers.js. Read the README.md for further instructions, implement the methods in the answers.js, passing the tests in the tests.js file. The answers has a

Quick tip: To run any of the exercises below in watch mode, add -- --watch, (e.g. npm run 01-making-promises -- --watch)

You are free to look at any of the tests for guidance, but don't change them.

Outline

The Promise Toolbox

These exercises are all about learning the mechanisms that we can use to create, transform, and combine promises.

• npm run 01-making-promises - Create promises with Promise.resolve, Promise.reject, and the Promise constructor.
• npm run 02-consuming-promises - Use .then(cb) and .catch(cb) to respond to a promise completing and do something with the result.
• npm run 03-transforming-promises - Use .then(cb) and .catch(cb) to transform the results of async processes.
• npm run 04-chaining-promises - Use .then(cb) and .catch(cb) to chain async processes.

Promise Puzzles

Now it's time to use the tricks from above to solve some problems.

• npm run 05-callbacks - Turn callback-centric functions into promise-centric functions.