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Part 1: Asking Questions

3:10 with Jason Seifer

Now that we're familiar with loops and iteration, let's practice our knowledge by writing a simple contact list program.

Code Samples

Here is the code we write in this portion of the video.

First, we set up a contact list array:

contact_list = []

Next, we define the ask method. We're going to be asking the user for input quite a bit so the ask method will repeat the logic for us.

def ask(question, kind="string")
  print question + " "
  answer = gets.chomp
  answer = answer.to_i if kind == "number"
  return answer
end

The ask method takes two arguments and defaults to having the kind of answer be a string. This will let us return numeric values if we want.

Finally, we test the ask method:

answer = ask("What is your name?")
puts answer
  • 0:00

    [SOUND] Now

  • 0:04

    that we're familiar with Loops and Iteration, let's practice

  • 0:08

    our knowledge by writing a simple contact list program using Workspaces.

  • 0:13

    Now we're gonna write a simple contact list program, and

  • 0:17

    this is what it looks like.

  • 0:18

    It will ask what the person's name is, and then do we want to add a phone number?

  • 0:31

    And then, we'll enter a couple phone numbers.

  • 0:34

    We don't want to add another person, and it will print out the contact list.

  • 0:40

    So let's go ahead and get started.

  • 0:44

    Let's go ahead and create a new file and we'll call it contact_list.rb.

  • 0:55

    So first we will have our contact list be an array and let's set that up, up front.

  • 1:04

    We now have an empty array.

  • 1:07

    Now one thing that we're going to be doing a lot is asking the user a question.

  • 1:11

    Let's go ahead and create a method called ask, since we're going to be asking

  • 1:15

    questions so often, and we'll call this method ask.

  • 1:25

    Now let's go ahead and send in a couple arguments.

  • 1:30

    So we're going to ask a question, and we'll say that the kind

  • 1:37

    of question we're asking by default is going to be a string.

  • 1:42

    That's going to be what we want to get back from the user.

  • 1:45

    So let's go ahead and print the question plus a space,

  • 1:51

    which will give somebody time to respond.

  • 1:56

    Now, we will get the answer from standard input, remove any trailing white space,

  • 2:05

    and then we'll say the answer is going to be an integer

  • 2:11

    if the kind is a number.

  • 2:18

    And then we will return the answer.

  • 2:23

    Now let's just run this, and we'll just say answer equals ask, what is your name.

  • 2:34

    And since we gave it a kind of string, we don't need to enter that,

  • 2:40

    since it has what's called a default value of an argument.

  • 2:46

    And then let's just print out the answer and see what happens.

  • 2:52

    Okay, so we now know that we are getting back a variable from the ask method.

  • 3:01

    In our next video, we're going to go ahead and create the add contact method,

  • 3:07

    which is going to use the ask method which we just wrote.

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