Build a Grocery List Program: Part 1

3:15 with Jason Seifer

Now that we know how to use arrays and hashes, we're going to build a small program that makes a grocery list for us. In this video, we'll add methods to create our list and also add items to it.

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Here is the code we write in the video. Follow along using Workspaces!

def create_list
  print "What is the list name? "
  name = gets.chomp

  hash = { "name" => name, "items" => Array.new }
  return hash
end

def add_list_item
  print "What is the item called?"
  item_name = gets.chomp

  hash = { "name" => name }
  return hash
end

list = create_list()
puts list.inspect

0:00
[SOUND] Now that we know how to use arrays and hashes,
0:05
let's write a simple program that uses everything we've used so far.
0:12
We're going to do this over a few different videos, so
0:15
be sure to follow along using workspaces.
0:18
Okay, now that we know how to work with arrays and hashes, let's go ahead and
0:23
write a simple shopping list program.
0:26
So I've gone ahead and launched a new Ruby workspace.
0:30
Now, let's go ahead and create a new file.
0:33
And we'll call this shopping list.rb.
0:38
Now let's go ahead and create a shopping list.
0:42
We'll create a method that asks for the name of the list, and then,
0:46
we can return a hash of the name and the items inside of the shopping list.
0:54
So we'll call that method, create list.
1:00
Now let's go ahead and ask what the list's name is.
1:08
And we will take from standard input, the name of the shopping list and
1:13
remove any external characters from it that are white space at the end.
1:19
Now let's go ahead and return a new hash.
1:26
We will give the hash a key of name and a key of items.
1:34
Which is a new array.
1:36
And then, we'll go ahead and return this hash.
1:42
Now that we have a method to create the list, let's go ahead and
1:46
create a method to add an item to the list.
2:01
So now we're going to add a list item, and
2:03
we'll get the item name from standard input.
2:08
And then we'll create a new hash, and we can return that hash.
2:15
Go ahead and save that.
2:17
And now, let's go ahead and ask the user.
2:21
Or their list.
2:23
So we can say, list and then an equals sign, and
2:28
we'll call the method create list.
2:34
Now what that will do is ask the user for the name of the shopping list,
2:39
and return a hash with the key of name and the key of items, which is an array.
2:48
And let's go ahead and print out list.inspect.
2:53
Now let's click down in the console and run this shopping list program.
2:58
The list name is groceries.
3:01
Now we can see we've got this list hash,
3:05
with the name of what we input in an empty array for items.
3:11
In the next video, we'll start adding items to the list.

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Build a Grocery List Program: Part 1

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