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‫-: Hi. Within this lecture, we are going to see how

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‫we can leverage this init function in order to

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‫create these properties without initializing them.

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‫So I'm deleting these initializers

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‫and I'm going to do this inside of my init function.

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‫Okay? So rather

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‫than printing musician created I'm just gonna ask

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‫for some input in the init function.

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‫So I'm going to ask for name init, it'll be a string, okay?

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‫And again, an age init.

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‫This will be an integer and an instrument init.

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‫This will be, again, a string.

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‫So what I'm going to do,

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‫I'm going to take those values

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‫and I'm going to say name is now name init.

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‫Age is now age init, Okay?

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‫So you're gonna have to say name is equal to name init.

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‫Age is now age init.

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‫And of course the instrument is again, instrument init.

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‫You don't have to say init.

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‫You can just go for name.

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‫You can just go for whatever variable name you want.

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‫I'm just trying to differentiate them a little bit

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‫so you don't get confused.

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‫Okay? So whenever I create an instance of this class

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‫it will ask me for a name and age and instrument.

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‫So rather than defining those values

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‫after we create the object,

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‫now we can do this in the same line.

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‫So let me do an example.

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‫So if I say Let James and James is a musician

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‫it should have asked me there.

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‫So let me do comment B.

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‫Yep. This is asking right now.

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‫So let me do this from the beginning.

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‫Okay? So if I do command B, it'll get synchronized

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‫as I said before.

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‫Now it's giving me an error.

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‫It says that you have a missing argument in here.

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‫Now if you open parenthesis, you will see that it asks you

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‫for a name init, age init, and instrument init.

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‫So for name, you can go for James, okay?

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‫For age, you can go for 50.

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‫And for instrument, you can go for guitar.

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‫So now if I print James dot age, it'll give me 50.

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‫So that's how you create objects with initializers.

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‫Okay? And while we are added,

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‫I believe we should learn about enums as well.

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‫So enums make our life easier

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‫when we try to categorize things.

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‫What do I mean?

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‫For example, if I want to add a type of musician in here

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‫as a property, I can just go and do

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‫that with a string right? But rather

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‫than doing a string, I'm just going to go for enum

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‫and you will see why, why I'm doing that in a clear way.

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‫So generally you see enums enumerated type declarations

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‫in the top of this project files, okay?

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‫So you have to give a name here

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‫an enum name, like musician type.

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‫And in here you write some categories.

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‫For example, our musician can be a vocalist, a guitarist

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‫or lead guitarist, right?

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‫So write them all.

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‫So lead guitar, it would be a vocalist,

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‫it would be a drummer, right?

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‫And it would be a bassist as well.

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‫So maybe you can think something

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‫like violinist or something. Okay?

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‫So why are we creating this types?

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‫We can have done this with strings as well.

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‫I'm going to show you why.

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‫If I come over here to my attributes

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‫I can easily add a new type.

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‫I can just say type, okay?

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‫And this would be a string, but if I do that

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‫my other developer working

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‫on this project can write vocal, okay?

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‫And the other developer using this class can write vocalist.

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‫And even if you are the only one working on a project

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‫like this, you can do the same mistake as well, right?

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‫You can go for vocal, you can go for vocalist.

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‫In some other cases

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‫maybe you want to standardize those types.

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‫So this is where enums come to play.

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‫You kind of standardize the category.

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‫So that will leave no room for mistake at all.

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‫So rather than saying this is going to be a string

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‫I'm going to say this will be a musician type. Okay?

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‫As you can see, musician type is a musician type type.

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‫So this is an enum, this is not a class

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‫but we can actually use this to choose a category.

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‫And now we have an error inside of

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‫init because we have to ask for a type init, right?

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‫So I'm going to go for type init

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‫and this will be a musician type rather than string.

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‫Now I can come over here

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‫and I can easily say my type, this type, okay?

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‫is going to be a type init.

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‫So right now we have created a category for ourselves

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‫and we have assigned it to be a property in our class.

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‫So let me do a build.

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‫So it'll get synchronized,

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‫and once it gets synchronized, as you can see

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‫we got another error in here.

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‫So it says

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‫that you have to add a new parameter here called type init.

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‫If you hit fixed, this will be added automatically.

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‫So I can hit that here

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‫and I can choose one of the categories that we have created.

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‫So I can easily come here.

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‫I can say, James is a vocalist, for example.

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‫And now I can reach this value as well, right?

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‫So let me try to print this James dot type.

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‫Now I will see the type in the logs as well.

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‫So this is how you use enums.

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‫This is how you leverage enums in your classes.

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‫If you're looking for a way to create categories,

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‫rather than doing this with a string,

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‫you can do this with enums,

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‫and this would be much more efficient

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‫much more safer than doing this with a string.

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‫So that's all for right now.

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‫We are going to stop here actually

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‫and within the next lecture

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‫we are going to see how we can add some actions

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‫some functions to our class as well.