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

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

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Build a Grocery List Program: Part 1

Code Samples