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All right, guys, in this module, we're going to be talking about Advanced Swift Properties.
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Now, previously, we've already seen what properties are
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and we've been using it throughout the course. Now, when we looked at objects and classes, we learned that
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properties can be a constant or it can be a variable, and they allow us to store data relating to a particular
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object or a class.
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So, for example, in this case, we've got a car object that has a color property that's equal to red and
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a type property that's equal to "coupe."
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It doesn't matter if it's a constant or variable, they're both properties.
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Now, more specifically, these types of properties can be described as stored properties because, essentially,
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they're just a container that can take a value and you could store it inside the container.
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And when you later need to use this stored property, you can take out the value and use it.
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Now, in this lesson and others in the module, we're going to be talking about a different type of property,
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and these are called computed properties.
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And what these allow us to do is to create properties whose values can be calculated on the go by using
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the code that we write and that will make it really similar to an Excel spreadsheet.
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So for example, if we were trying to work out the area of a particular wall, say, in our bathroom, and we
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actually recorded it wrong, instead of being 1.5 by 2.6 meters, actually, that wall height was 2.3 meters.
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Well, then in that case, the area can auto-update and be calculated or computed based off the change in
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the height,
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and this is exactly what we're going to do with our code. And the code that we're going to write is going
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to be super useful because we're going to use it to solve the biggest issue that mankind has which is,
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of course, how many pizzas should you buy, so that you can feed everybody who's in your house.
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This has mystified mankind for a long time.
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And finally, we're going to be able to use computed properties to solve this problem.
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So once you're ready, head over to the next lesson and we'll get started right away.