JS Practice — Built-in Objects

String.prototype.search() — vs indexOf comparison

📖 Usage Example

'hello world'.search(/world/)   // → 6
'hello'.search(/d/)           // → -1
'abc123'.search(/[0-9]/)       // → 3

Use search() to find the index of the first regex match in a string, returning -1 if not found.

String.prototype.search() vs indexOf

Both return the index of a match or -1. search accepts regex; indexOf accepts only strings.

Challenge: Implement firstLetterIndex(str) that returns the index of the first letter using search.

firstLetterIndex('123abc') // → 3
firstLetterIndex('hello')  // → 0

💡 Hints (1)

• `str.search(/[a-zA-Z]/)` behaves like `str.indexOf` for literals but supports patterns.