JS Practice — Built-in Objects

String.prototype.startsWith() — with position param

📖 Usage Example

const str = 'Hello, World!'
str.startsWith('Hello')         // → true
str.startsWith('World')         // → false
str.startsWith('World', 7)      // → true

Use startsWith() to check if a string begins with a specific prefix, with an optional start position.

String.prototype.startsWith() — Position Parameter

The optional second argument position specifies where to start the search.

Challenge: Implement startsAtPos(str, search, pos) that checks if str starts with search at position pos.

startsAtPos('hello world', 'world', 6) // → true
startsAtPos('hello world', 'hello', 6) // → false

💡 Hints (1)

• The second argument shifts the starting position of the search.