JS Practice — Built-in Objects

Array.prototype.indexOf() — find word index

📖 Usage Example

const words = ['cat', 'dog', 'bird']
words.indexOf('dog')   // → 1
words.indexOf('fish')  // → -1

Use indexOf() to find the index of a specific string in an array.

Array.prototype.indexOf() — strings

indexOf works with string arrays too, using case-sensitive strict equality.

Challenge: Implement findWord(words, word) that returns the index of word in the array.

findWord(['foo', 'bar', 'baz'], 'bar') // → 1
findWord(['foo', 'bar'], 'qux')        // → -1

💡 Hints (2)

• `indexOf` is case-sensitive — `"hello" !== "Hello"`.
• For case-insensitive search, you would need `findIndex` with a `.toLowerCase()` comparison.