JS Practice — Built-in Objects

String.prototype.toLocaleLowerCase() — already lowercase

📖 Usage Example

'HELLO'.toLocaleLowerCase()   // → 'hello'
'WORLD'.toLocaleLowerCase()   // → 'world'
'ABC123'.toLocaleLowerCase()  // → 'abc123'

Use toLocaleLowerCase() to convert a string to lowercase using the locale-specific rules of the host environment.

String.prototype.toLocaleLowerCase() — Already Lowercase

If the string is already lowercase, toLocaleLowerCase() returns an equal string.

Challenge: Implement ensureLower(str) and verify it works on already-lowercase strings.

ensureLower('hello') // → 'hello'

💡 Hints (1)