45 lines
956 B
Markdown
45 lines
956 B
Markdown
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---
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title: Classes
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---
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# Classes
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### Basic Usage
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#### Declaration
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`class` keyword is used to define the class
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It is consisted of: class name, class header (type parameters, constructor) and class body (curly braces)
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```kotlin
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class Person { ... }
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```
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#### Constructor
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There are multiple ways to define class constructor.
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Primary constructor is part of the class header (name field with data type):
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```kotlin
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class Person(name: String) { ... }
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```
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Secondary constructor: using `constructor` keyword inside class body
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```kotlin
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class Person {
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constructor(parent: Person) {
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parent.children.add(this)
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}
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}
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```
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#### Usage
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Class instance can be created as regular function
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There is no need for `new` keyword
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```kotlin
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val john = Person("John Wayne")
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```
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#### Resources
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* [Basic Syntax Reference](https://kotlinlang.org/docs/reference/basic-syntax.html)
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* [Kotlin Classes Reference](https://kotlinlang.org/docs/reference/classes.html)
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