Array#splice

let arrDeletedItems = array.splice(start[, deleteCount[, item1[, item2[, ...]]]])

let myFish = ['angel', 'clown', 'mandarin', 'sturgeon']
let removed = myFish.splice(2, 0, 'drum')

// myFish is ["angel", "clown", "drum", "mandarin", "sturgeon"] 
// removed is [], no elements removed