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Okay, so we've got our contact, phone
number, and address classes all set up.

2
00:00:05,470 --> 00:00:09,480
Now our contact when we
initialize it has addresses and

3
00:00:09,480 --> 00:00:14,030
phone numbers, but remember we're
building an address book here.

4
00:00:14,030 --> 00:00:18,060
So an address book is going
to have many contacts.

5
00:00:18,060 --> 00:00:23,298
Now let's go ahead and represent
an address book with another class.

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00:00:23,298 --> 00:00:29,879
So once again, do New File, and
we'll call this address_book.rb.

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And this will be an address book class.

8
00:00:38,620 --> 00:00:42,660
Now just like we did with our contacts,
having addresses and

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phone numbers,
when we initialize an address book class,

10
00:00:50,330 --> 00:00:53,250
we'll have our contact be an empty array.

11
00:00:53,250 --> 00:00:56,895
And that's gonna be an instance variable.

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00:00:56,895 --> 00:00:59,944
So any method in address book
is going to have access to it.

13
00:01:02,064 --> 00:01:06,990
Now, so that we don't have
to use the at sign each time

14
00:01:06,990 --> 00:01:09,945
we want to refer to the contact,

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00:01:09,945 --> 00:01:14,911
we'll say we have an attribute reader for
contacts.

16
00:01:14,911 --> 00:01:20,474
And let's go ahead and
create a method to print our contact list,

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and then we can just iterate
through the contacts.

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And we'll print out our contact, and we
can use the last name, first name format.

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So now that we have
the address book class set up,

20
00:01:48,750 --> 00:01:52,860
we can instantiate one, and then let's
go ahead and add a contact to it.

21
00:01:55,630 --> 00:01:59,758
And actually I think I can just
grab this from our contact file.

22
00:02:02,078 --> 00:02:08,318
I'm gonna copy that, And paste it,
and then I can take it out of here,

23
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So that it's not cluttering up
the output like we had before.

24
00:02:20,619 --> 00:02:24,624
So now we can say address_book.contacts,
and

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we will add this contact
that we just created.

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00:02:33,799 --> 00:02:36,398
And now we can print
the contact list as well.

27
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And let's just say Contact List.

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00:02:44,919 --> 00:02:52,230
Okay, now let's run address_book.rb,
and this is not gonna work correctly.

29
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Can you guess why?

30
00:02:54,720 --> 00:02:59,180
And here we get the message
uninitialized constant Contact.

31
00:03:00,460 --> 00:03:06,250
And the reason is we haven't told Ruby
that we're gonna be using that class.

32
00:03:06,250 --> 00:03:10,060
So we have to do it the same way that we
did in the contact class where we require

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00:03:10,060 --> 00:03:11,409
phone numbers and addresses.

34
00:03:12,800 --> 00:03:18,899
We have to tell our address book,
To require contacts.

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00:03:21,578 --> 00:03:25,139
So let me clear my screen here and
print this again.

36
00:03:25,139 --> 00:03:27,730
And hey, here we go.

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Our contact list now has my name on it.

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00:03:33,049 --> 00:03:37,209
And go ahead and just add another contact.

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00:03:42,208 --> 00:03:44,149
Just to make sure it all prints correctly.

40
00:04:18,586 --> 00:04:19,720
Okay.
And one more time.

41
00:04:21,640 --> 00:04:22,370
All right.

42
00:04:22,370 --> 00:04:24,980
So far,
our contact list is looking pretty good.