Promise chaining in Javascript - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to add a handler that logs the resolved value of the promise.

Javascript

Promise.resolve('Hello').[1](value => console.log(value));

Drag options to blanks, or click blank then click option'

Athen

Bcatch

Cfinally

Dresolve

Attempts:

3 left

💡 Hint

Common Mistakes

Using catch instead of then to handle success.

Using finally which does not receive the resolved value.

Trying to call resolve on the promise instance.

The then method is used to handle the resolved value of a promise.

2fill in blank

medium

Complete the code to chain a second then that doubles the number.

Javascript

Promise.resolve(5).then(num => num).[1](num => num * 2);

Drag options to blanks, or click blank then click option'

Aresolve

Bfinally

Ccatch

Dthen

Attempts:

3 left

💡 Hint

Common Mistakes

Using catch instead of then for chaining.

Using finally which does not modify the value.

Trying to call resolve which is not a method on the promise instance.

To chain operations on promises, use then again.

3fill in blank

hard

Fix the error in the code by completing the blank with the correct method to catch errors.

Javascript

Promise.reject('Error occurred').[1](error => console.log(error));

Drag options to blanks, or click blank then click option'

Athen

Bfinally

Ccatch

Dresolve

Attempts:

3 left

💡 Hint

Common Mistakes

Using then which only handles success.

Using finally which does not receive error arguments.

Trying to call resolve which is not a method on the promise instance.

The catch method handles rejected promises (errors).

4fill in blank

hard

Fill both blanks to create a promise chain that adds 3 then multiplies by 2.

Javascript

Promise.resolve(4).[1](num => num + 3).[2](num => num * 2);

Drag options to blanks, or click blank then click option'

Athen

Bcatch

Cfinally

Dresolve

Attempts:

3 left

💡 Hint

Common Mistakes

Using catch in the middle of the chain which breaks the flow.

Using finally which does not transform the value.

Trying to call resolve which is not a method on the promise instance.

Both steps use then to process the resolved value sequentially.

5fill in blank

hard

Fill all three blanks to chain promises that fetch data, parse JSON, and log the result.

Javascript

fetch('url').[1](response => response.[2]()).[3](data => console.log(data));

Drag options to blanks, or click blank then click option'

Athen

Bjson

Dcatch

Attempts:

3 left

💡 Hint

Common Mistakes

Using catch instead of then for success handlers.

Trying to call json as a property instead of a method.

Missing parentheses after json.

Use then to handle promises, json() to parse response, and another then to log data.