JS Practice — Built-in Objects

String.prototype.includes() — empty string always returns true

📖 Usage Example

const str = 'Hello, World!'
str.includes('World')    // → true
str.includes('xyz')      // → false
str.includes('Hello', 1) // → false

Use includes() to check if a string contains a specific substring, with an optional start position.

String.prototype.includes() — Empty Substring

Every string includes the empty string ''.

Challenge: Implement alwaysTrue(str) that returns str.includes('').

alwaysTrue('anything') // → true
alwaysTrue('')          // → true

💡 Hints (1)