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Hey what's up everyone.

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Mark Price you're a dove slopes dot com.

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And today we're going to talk about inheritance not like the inheritance you got from your grandfather.

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You know when all your peers were out there working their butts off you know failing and failing and

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failing again and their Swetnam bleeding and you know you're out there and you get an inheritance and

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you're just like here's my Bugatti.

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You guys suck.

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Yes not one of those kind of things.

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It's a little bit different.

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It's more so like an inheritance of features more like I have red hair because my grandfather has red

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hair.

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You've inherited some type of features from some type of relative.

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So I'm going to get started with the playground and we're going to call this in heritance inheritance

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it's one of those words that's easy to misspell.

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Inheritance is a principle of object oriented programming.

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OK.

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Object oriented programming.

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So a perfect example is continuing on with a car or a vehicle.

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We've got to view class and a vehicle class has some basic features list.

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We'll go ahead and say like var tires equals four.

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You've seen something like this before and then bar you know make of type string.

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But right now there's nothing in a bar model of type string.

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OK.

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And we said phunk drive and then we can say phunk for aik OK and save our current speed of type let's

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say double.

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And we started off at zero.

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The car's not moving.

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And so may be OK.

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Let's say let's say you are creating can complex drive algorithm where it's going to move accelerate

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the car forward.

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So we pass in the speed increase of type double and then maybe the base.

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So for a basic car the basic algorithm is this it is this current speed OK.

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Plus equals speed increase times.

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Let's say two let's say that was the algorithm some random arbitrary algorithm.

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The current speed of the vehicle equals the current speed plus speed increase times two.

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OK.

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Now this going and create what's called a subclass.

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OK so this is a class let's create a subclass.

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We're going to show inheritance here.

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So a class

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what do I want to say class BMW.

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OK class BMW or even better.

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How about a sports car.

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Just for fun sports car inherits from vehicle so you start inheritance by putting a colon here and then

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specifying the type K which is this.

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This is the type the type or class that you want to inherit from.

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Now this is really cool there's nothing in here right nothing at all.

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But you can still access the properties of the parent class so on this sports car you know tires are

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going to stay the same.

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But you know maybe we can set the make and model.

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So I don't have to recreate those which is really cool I can say make equals and let's say BMW and model

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equals the say three series.

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OK.

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So we've got to make an a model.

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What we need to do here actually is create an initialiser first like so.

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All right and then and here we can set our make and our model like so is yelling at us because it wants

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us to override it.

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So we need to call super in it super It just some boilerplate stuff you've got to do in every class.

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OK.

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So every single class has by default an initialization function but you don't see it right here because

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we did not implement it.

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So let's implement it.

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Now on the parent class OK.

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So we've got to initialize initialiser on the parent class.

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And initialiser here in the subclass.

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And this is interesting.

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We're calling super init on the parent class.

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What does that even mean.

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Well let's print this out.

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I am the parent.

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OK.

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And then just print this down here.

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I am the child and what I want to do is just create an instance of this class penning the X code doesn't

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crash on us.

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It crashed.

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So OK.

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But I want to do is create an instance of the sports car so let car equals a new sports car.

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And what's interesting.

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Fit aside soloed I am the parent Prince and I am the child of what's happening here.

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So we create the sports car and then this initialiser is called and the override function says I want

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to override the parents initialiser function.

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So it won't be called at all but then we actually call here explicitly.

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So then that's going to go back up to the parent class and call was whatever in it.

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So sometimes parent classes have set up or things like that and introduce We want to call it.

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It's typical to call the parent class and then to create your own functionality which is really cool.

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OK so here's our sports car.

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Awesome.

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Now let's our sports car needs to drive faster than the standard algorithm.

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So what we can do is we can even override the functions so I can type and drive.

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That's going to override it.

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And now what I could do instead of current speed being equal to this I can say current speed plus equals

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speed increase times three.

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So this one is times too but this was times three.

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And now the child's class we know that every car needs to have a drive function.

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And so that's great.

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Like why would we we wouldn't want to create a bunch of different classes and re-implement this function

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every single time.

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So it's already pre-built and we just wrote it once and we overwrote it here which is great.

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Every vehicle needs to be able to drive but its implementation could be different purview.

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Is a Ford F-150 going to accelerate differently than a Ford Mustang.

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Yes every car is going to have its acceleration.

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Therefore it would have its own code here in the functions that it's overriding.

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And of course you can override the properties as well too.

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So the whole point of this lesson we could go way down this rabbit hole where we're not going to.

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The whole point of this lesson to know is that you can create a parent class and children classes can

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inherit from that parent class and you can do more than one.

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So if we bought a sports car we could say class truck inherits from view acle we could have done the

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exact same thing there.

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And then you know initialiser or let's let's just copy what we got here.

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Let's make it real easy so it doesn't yell at us.

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OK.

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And you know we can get rid of these here OK and then a trunk a truck could have its own drive function

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that you know speed increase you know plus equals or no excuse me current speed plus equal speed increase.

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You know without multiplying it by no multiplier.

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And so anyway now we've got two different classes here that both inherit from Buca they both have a

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drive function but their implementation is different and why this is important is because it helps you

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create objects that can adapt to different situations.

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For instance you know on Instagram you may have a parent class that has you know a specific base filter

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but then you may have different filters like Valencia and other things that have their own algorithms

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that they need to implement.

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So rather than putting it all one giant class file it could easily have created a parent class which

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creates a deeper filter and then they can override it and add some other functionality to it for those

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specific filters.

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Again all kinds of things you can do with classes objects and inheritance but that's all you need to

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know now you're going to learn about it more as you use it in Aiwass development so.

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Mark Price your DENSELOW dot com.

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Movin on and.