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Creating a Class
3:56In this video, we create a simple class. The class will be modeled after the concept of a name and return the different attributes a name might have.
Now that we know a little bit about how
objects and
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classes work, let's create our own class.
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We'll start small and create a class for
representing a name.
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Before we jump straight in to coding, let's
think about how a name can be structured.
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We're not going to get into everything
that can be possible with a name.
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But for the purposes of the class we're
going to write, a name could have
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the following items, title, first name,
middle name, and last name.
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We create a class using the class keyword,
and
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then the name of the class that we wanna
create.
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Let's see how that works now using Work
Spaces.
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So let's go ahead and create our first
class.
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I've launched a Ruby Workspace here, and
on the left,
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I'm going to right click and choose new
file.
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And we'll name this name.rb.
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And this is gonna be a simple class that
just returns my name.
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So let's go ahead and dig in.
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We start writing a class by using the
keyword class.
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Then we type the name of the class.
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Using an uppercase letter to start with.
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In this case, the class name is going to
be Name.
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[SOUND] And then we close it, by writing
end.
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Now, if we wanted to have a longer class
name, that was more specific,
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the convention behind that is doing
something like,
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say, FirstName with no spaces.
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But we're just gonna keep the name class
here, and let's go ahead and
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think about the different components of a
name.
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First we'll start with the title and
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we're gonna create methods for all of
these different attributes.
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And we'll say title and I'll go with
"Mr." this is a String.
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And I have a first name, that's Jason.
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[NOISE] I don't have a middle name but
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I'm going to return an empty string and
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I do have a last name, and that's going to
return "Seifer".
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So now that we have this class written,
let's go ahead and instantiate it.
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And let's just print out the name.
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Go ahead and click into the console and
type ruby name.rb.
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Now this returned, well, pretty much
nothing it has the name of the class, and
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a colon, and a bunch of weird symbols
here.
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And this is actually the address in memory
of the instantiated object.
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But let's go ahead and
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actually do something with the data that
we have inside here.
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So we'll print out the title.
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We're just calling a method.
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[SOUND] And now we are calling all of
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the different methods of this name object
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which is an instance of the Name class.
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Now let's run this again and see what
happens.
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And it did exactly what we expected.
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And print it out.
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The results of these different methods.
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