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So in this lesson we're going to talk about enumerations or what we call EON's you know is that essentially

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a way of time close sooner or related values with each other.

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So it becomes what we call a typesafe what it means is it means you have values such as south east north

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and west and you put all of them inside one value called let's say direction and then we can get direction

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dot south and direction that North.

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And the reason it is safe is simply because we have to use the dot operation because of that is constrained.

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We cannot accidentally right a wrong value in there.

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So we don't mind this go ahead and get started in ex-coach and see how you're going to do this.

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When I go to explore I start a new project let's call it informs us with might you know I'm safe I'm

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going to go ahead and say get rid of all of that as usual.

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So if you remember earlier on in some of our previous lessons we're talking about a an application that

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essentially is a real estate listing application and we said some of the listings are for sale.

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Some of them are for rent.

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So here is a vivid example of how to use enormous here.

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I'm going to say you know let's call it the property type and it has two cases case sale and case are

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right.

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So I have two types.

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One of them is for sale.

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One of them is for rent.

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Now let's see how we're going to use that.

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And why go ahead and say class and my classes property doesn't have a superclass.

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And yet I have a variable let's say address which is a string.

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And I have a variable type Ritchies proper type.

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And of course if I try to initialize this I have to say in its e-mail address which is a string as all

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dates and type which is proc type and of course self that address becomes empowered dress and self that

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type certainly becomes proper type or type site type.

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So simple as that.

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So every time we are making a property our right off the bat based on a kind of strange enough we can

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choose which one of these two conditions is that.

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So here again go ahead and say where this property is going to be a property that property is going

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to be an actress.

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Let's say take the street and then the input type is going to be propped type Perabo type dot Brant

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for instance.

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So I know this one is for rent.

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And now if you want to use this I could go ahead and say for instance if this was a member of an array

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and you were running a search now you can do all of those things yourself.

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I could say if this property dot product type is Propp type dot say it for instance then let's say display

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this or whatever that you think you want to be doing with it.

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So that's essentially the core concept of enumeration or enough times.

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So before I finished this lesson there is one more kind of Islam that I want to show you one that's

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enumeration Veit case.

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I tried to state.

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So here's how we do those.

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I'm going to go ahead and say you know I mean all our cities and it is.

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CHACE I treatable.

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And then the cases are Vancouver Sun from New York.

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And then I'm going to go ahead and say for let's call it city in cities all cases of Prince city for

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me.

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And that's about that.

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I can iterate through the objects in my cities through the chases in my enumeration.

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So as you mention very useful info and values are related to each other and you want them to be typesafe.

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So you know specifically which one you're choosing you're choosing property type data sale and you can

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obviously use those for a variety of purposes would end up seeing this happening more and more as we

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go through real applications.

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So our eyes should see you guys in the next lesson I guess.