Can Class name be used as type of variable declaration

1

class SmartTvDevice : SmartDevice() {
}

class SmartHome(val smartTvDevice: SmartTvDevice) {

}

I have a question in the above syntax where Val smartTvDevice is mentioned. After colon the name SmartTvDevice is a type for variable. But I learned only these types in kotlyn docs. String, float, Boolean, int. Is class name can be used to for type? Thank you

2

Yes. Classes define their own types. I’d urge you to check out the documentation, especially the Classes section

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3

Also see the StackOverflow question What is the difference between types and classes in Kotlin?, which covers this. (Disclaimer: one of the answers is mine :​-)

In particular, while many classes are types, some aren’t (e.g. generic classes, which need type parameters to be specified), and some types aren’t classes (e.g. interfaces, or classes with a trailing ? indicating a nullable type).

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