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Now that we can add things to arrays and
get things back out of arrays,

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wouldn’t it be useful if we could
also remove things from arrays?

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Let’s take a look at how that
works now using workspaces.

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Okay, so let's launch irb again
inside of a Ruby workspace.

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And we'll set up our grocery_list array.

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So we'll give this a few
different items here.

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All right, now if we want to get
to the last item in this array,

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let's go ahead and assign that
to a variable called last_item.

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And we'll use the pop method,
which returns the last item in the array,

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and removes it from the original array.

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That's the big difference between
the last method and the pop method.

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So if we look at the last item here,
we'll say grocery_list.pop.

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Now our variable last_item
has the string "potatoes", but

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if we look in our grocery_list this time,
it is now lacking "potatoes".

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Similarly, there's another method called
shift, which returns the first item.

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So we'll look at
the grocery_list array here.

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And we'll call the shift method on it.

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Now, it we look at our first item,
it contains the string "milk".

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And if we take a look at our grocery_list,

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it now only has four items in it,
"eggs", "bread", "ice cream", and "pie".

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So we've already done some shopping here.

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Now let's say we wanted to take two
items off of this grocery_list.

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Let's create a variable
called drop_two_items.

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And we'll say grocery list,
the method drop, and the number 2.

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Now let's go ahead and
look at our drop_two_items variable.

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It contains "ice cream" and "pie",
the last two items in the array.

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Now let's take a look at our grocery_list.

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The grocery list was not
modified by the drop method and

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still has everything inside of it.

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Gonna clear my screen here.

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Let's take a look at our grocery_list.

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Now here's another cool thing.

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If we want to add onto the beginning
of the array, just like

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we took from the beginning of the array
earlier, we could use the unshift method.

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So, let's say, grocery_list.unshift,
and we'll give that "milk".

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Now our grocery_list has
"milk" on the front of it.

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And let's go ahead and
put "potatoes" back on there.

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All right, now we have a pretty
decent grocery list to work with.

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I'm going to clear my screen again,
and that's our grocery list.

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And let's say we wanted the first
three items from this grocery list.

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We could use the slice method.

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So let's say,
first_three_items = grocery_list.slice.

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Now we give it the index, which is 0, and
the number of items we want, which is 3.

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Now first_three_items contains "milk", 
"eggs", and "bread",

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and our grocery_list was
unmodified by the slice command.

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Now we could give it any index we wanted.

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So we could say new_list is
grocery_list.slice and then any index.

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Let’s give it the index of 2.

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And say we only want 2 items, and
that's gonna be "bread" and "ice cream".

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Now that's what our new
list contains as well.

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Try removing things from arrays
now on your own, using Workspaces.