JS Built-ins
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ArrayArray.prototype.popintermediate

Array.prototype.pop() — verify array is mutated

📖 Usage Example
const arr = ['a', 'b', 'c']
arr.pop()
console.log(arr)  // → ['a', 'b']  (mutated!)

pop() mutates the original array — if you need immutability, use slice(0, -1) instead.

Array.prototype.pop() — mutation

pop() is a mutating method: it changes the original array. After popping, the array has one fewer element. This exercise focuses on observing that side-effect.

Challenge: Implement popAndCheck(arr) that pops from arr and returns the mutated array (not the popped value).

popAndCheck([1, 2, 3]) // → [1, 2]
popAndCheck([10])      // → []
💡 Hints (2)
  • • Call `arr.pop()` and then `return arr` — the array has already been mutated.
  • • Note that the returned array is the **same object** as the input.