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In the last video we reflected our interface to have a little bit more generic name.

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We did the same thing with our function down here.

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So now I want to do something kind of interesting inside this file.

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Right now we've got a object called old Civic on a define another new object right underneath it.

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Am I going to call this something like drink.

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No just a couple of videos ago we did some examples on drinks and we said that a drink had like a color

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and carbonated and some other thing like that.

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Let's try expressing a drink object right here with some of the same properties.

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Something like maybe give this thing a color that is brown and maybe carbonated carbonated and it'll

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be a Boolean true and then maybe it will also have like that sugar content and that's really supposed

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to be like number in grams.

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So like 40 grams of sugar and then I'm going to give this one more property I'm gonna give it a summary

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property summary is going to be a function anytime we call it it's going to return a String and so inside

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of here I'm going to return something like My drink is or how about has and then this dot Sugar grams

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of sugar and that's reasonable.

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Once again notice that I'm using back to X here to form up this string All right so here's what gets

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really interesting here is like the entire point of interfaces if you don't get this quite right away

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I'm going to show you a couple diagrams to really help you understand what's going on but here's what's

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going on.

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Notice how our old civic function has a summary function tied to it or some old Civic object has a summary

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function tied to it our drink object also has a summary function tied to it.

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These two objects right here represent very different things inside of our application but they both

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have a summary function that returns a string.

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That means that they are both considered to be reportable types so because they both have a property

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called summary that is a function that returns a string.

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This is of type reportable and this is of type reportable because they are both of type reportable we

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can use both old Civic and drink with the function we defined down here so I can call print summary

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with old Civic I can also call print summary with drink as well and it works equally well with both

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of these very different objects.

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So what's the big point here.

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The point is that we can use a single interface to describe the shape or the different properties of

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very different objects when we do so we can have those objects implement different properties or different

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functions and by doing so we can make these very different objects interact with different functions

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that we create like print summary right here so this encourages us to write somewhat generic looking

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functions.

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Notice how this is now print summary.

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Would it have made sense to have this be like print vehicle and then pass and drink to it.

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No I don't think that would have not made a lot of sense.

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So instead we decided to make a somewhat generic looking interface that described what we had to do

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in order to call this function right here.

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Gonna change that back to print summary by the way so in doing so we've now got a much more reusable

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function inside of our application.

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This function can be used with any type of object that satisfies the reportable interface and this feature.

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This right here is what is going to encourage us to write more reusable code with typescript.

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Now I know this is like a super basic example and it's very contrived but I just want this to be your

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first taste of how we're going to use interfaces in general now to make sure everything is super crystal

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clear here.

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Let's take a quick pause in the next video we're going to kind of reiterate what we did and what the

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entire point of this application was.

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We're going take a look at a couple of different diagrams to help you understand what's going on and

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we'll move on to our next subject where we're going to very quickly continue to see what the power of

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interfaces is inside of our applications.

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So quick pause and I'll see you in just a minute.