[NB] I did not write this content: This content is not mine, it is copied straight from the website referenced in the link:
apply to append an array to another
We can use
push to append an element to an array. And, because
push accepts a variable number of arguments, we can also push multiple elements at once. But, if we pass an array to
push, it will actually add that array as a single element, instead of adding the elements individually, so we end up with an array inside an array. What if that is not what we want?
concat does have the behaviour we want in this case, but it does not actually append to the existing array but creates and returns a new array. But we wanted to append to our existing array... So what now? Write a loop? Surely not?
var array = ['a', 'b'];
var elements = [0, 1, 2];
apply to the rescue!