JS Practice — Built-in Objects

Object.entries() — order matches Object.keys

📖 Usage Example

// Get [key, value] pairs of an object
const obj = { a: 1, b: 2 }
Object.entries(obj)   // → [['a', 1], ['b', 2]]

Use Object.entries() to get an array of [key, value] pairs for iterating over an object's own enumerable properties.

Object.entries() — consistent ordering

The order of entries from Object.entries matches the order of keys from Object.keys. Both follow insertion order for string keys.

Challenge: Implement entryKeys(obj) that returns just the keys from Object.entries (the first element of each pair).

entryKeys({ b: 2, a: 1 }) // → ['b', 'a']

💡 Hints (1)