Why signals are introduced in Angular - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a signal in Angular.

Angular

const count = [1](0);

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

Asignal

BuseState

Cref

Dreactive

Attempts:

3 left

💡 Hint

Common Mistakes

Using React hooks like useState instead of Angular signals.

Using ref which is from Vue, not Angular.

In Angular, signal is used to create reactive state that updates the UI automatically.

2fill in blank

medium

Complete the code to update a signal's value.

Angular

count.[1]((prev) => prev + 1);

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

Aset

Bupdate

Cnext

Dchange

Attempts:

3 left

💡 Hint

Common Mistakes

Using set which replaces the value directly, not updates it.

Using non-existent methods like next or change.

The update method changes the signal's value based on the current value.

3fill in blank

hard

Fix the error in the code to read a signal's value.

Angular

const current = count[1];

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

A.get()

B.value

C[]

D()

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to access a property like .value which does not exist.

Using square brackets which are invalid here.

Signals are functions, so to get their value you call them with ().

4fill in blank

hard

Fill both blanks to create a computed signal that doubles the count.

Angular

const doubleCount = [1](() => count() [2] 2);

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

Acomputed

B*

C+

Dsignal

Attempts:

3 left

💡 Hint

Common Mistakes

Using signal instead of computed for derived values.

Using addition + instead of multiplication.

computed creates a signal derived from others. Multiplying count by 2 doubles it.

5fill in blank

hard

Fill all three blanks to create a signal, update it, and read its value.

Angular

const score = [1](10);
score.[2](prev => prev [3] 5);

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

Asignal

Bupdate

C+

Dcomputed

Attempts:

3 left

💡 Hint

Common Mistakes

Using computed to create the initial signal.

Using set instead of update when a function is passed.

Using subtraction - instead of addition.

Create a signal with signal, update it with update, and add 5 using +.