js-splice.js

// splice( starting-index, delete-count, new-item)
// start is index exact, delete-count is how many elements to remove including start
// new-item is optional and is added at starting-index
// splice is permenant
var dogs = ["Pit Bull", " American Cocker Spaniel", "Beagle", " Belgian Malinois"];
var newDog = "Bloodhound";
var guideDog = "Brussels Griffon"

// take out Beagle
dogs.splice(2,1);
console.log("dogs - beagle:", dogs);
//add newDog after Pit Bull
dogs.splice(1,0,newDog);
console.log("newDog after Pit Bull:", dogs);

// change one out swap dogs 
// swap guideDog for Pit Bull
dogs.splice(0,1,guideDog);
console.log("dogs swap guideDog for Pit Bull:", dogs);