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You can also implement inheritance in interfaces.

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Let's say we have another interface named and this is the interface which actually makes sure that we

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have a name property.

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So now a here in person we could implement readable and named to be forced to have both agreed method

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and a name that is something we could do or if we know that agreeable things Greta all objects always

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need to have a name.

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We could make sure that this readable interface actually extends to named interface so that together

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they form a new interface which forces every object based on the readable to have a grid method but

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also to have a name and to do that we can add extends here on the interface as well and we extend named

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now therefore as I said this forms a new interface which is in the end the interface that forces us

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to have a great effort but not just yet.

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It also forces us to have everything.

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The named interface defines in this case a Name property.

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So if a would remove name here I would already get an error because this class now incorrectly implements

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the interface readable because the property name is missing.

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So that's also how we can combine interfaces.

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Why would we split an interface like this.

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Well maybe you have an application where on some objects you only want to force them to have a name

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and not agreed method.

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Whereas on other objects you need both greet and name.

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With this split this is possible some objects or some classes can just implement named and others can

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implement reasonable and are forced to have both greet and the name.

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So extending interfaces is possible.

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And there you can also extend more than one so you can merge multiple interfaces into one single interface.

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We could merge and no interface.

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If we had it simply separated with a comma remembered at four classes this was not possible.

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When you use classes and inheritance you can only inherit from one class you can't inherit from multiple

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classes for interfaces that is different for interfaces you can indeed inherit from multiple interfaces.

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Because in the end they're all just getting merged together.

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And in this pure type of feature which is actually not translated to JavaScript as you will see we can

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de offer for break the rules set up for JavaScript classes and extend multiple interfaces.