Satisfies operator in Typescript - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to use the satisfies operator to check the type of the object.

Typescript

const user = { name: "Alice", age: 30 } [1] { name: string; age: number };

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

Asatisfies

B:

Cas

Dimplements

Attempts:

3 left

💡 Hint

Common Mistakes

Using ':' instead of 'satisfies' which only declares type but does not check compatibility.

Using 'as' which changes the type instead of checking it.

The satisfies operator is used to check that the object matches the given type without changing the type of the object.

2fill in blank

medium

Complete the code to ensure the object matches the interface using the satisfies operator.

Typescript

interface Product { id: number; name: string; }
const item = { id: 1, name: "Book" } [1] Product;

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Aimplements

Bextends

Cas

Dsatisfies

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'implements' which is only valid in class declarations.

Using 'as' which casts the type instead of checking compatibility.

The satisfies operator ensures that 'item' matches the 'Product' interface without changing its type.

3fill in blank

hard

Fix the error in the code by using the correct operator to check the type compatibility.

Typescript

const config = { debug: true, version: "1.0" } [1] { debug: boolean; version: string };

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A:

Bsatisfies

Cimplements

Das

Attempts:

3 left

💡 Hint

Common Mistakes

Using ':' which only declares type but does not check compatibility.

Using 'as' which casts the type and may hide errors.

Using 'satisfies' checks that 'config' matches the type without changing its type, fixing the error.

4fill in blank

hard

Fill both blanks to create a typed object that satisfies the interface without changing its type.

Typescript

interface User { id: number; username: string; }
const newUser = [1] [2] User;

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A{ id: 5, username: "john" }

Bas

Csatisfies

D:

Attempts:

3 left

💡 Hint

Common Mistakes

Using ':' instead of 'satisfies' which only declares type.

Using 'as' which casts the type and changes it.

The object literal is assigned and checked with 'satisfies' to ensure it matches the User interface without casting.

5fill in blank

hard

Fill all three blanks to create a constant object that satisfies the type and access its property safely.

Typescript

type Settings = { theme: string; notifications: boolean };
const settings = [1] [2] Settings;
const theme = settings.[3];

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A{ theme: "dark", notifications: true }

Bsatisfies

Ctheme

Das

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'as' instead of 'satisfies' which casts the type.

Accessing a property name that does not exist.

The object literal is checked with 'satisfies' to ensure it matches the Settings type, then the 'theme' property is accessed.