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39 lines
947 B
Markdown
39 lines
947 B
Markdown
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---
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id: 3b88db70-6291-45e3-96da-3fb70a43222a
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title: JavaScript Class Inheritance
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---
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# Example
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Classes in JavaScript can inherit from each other
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``` javascript
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class Parent {
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constructor(name, parentChild = "Parent") {
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this.parentChild = parentChild
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this.name = name
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}
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speak(line) {
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console.log(`${this.parentChild} ${this.name} says '${line}'`)
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}
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}
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class Child extends Parent {
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constructor(name){
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super(name, "Child")
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}
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}
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let parent = new Parent("Father");
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let child = new Child("Gregory");
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parent.speak("Get off my lawn!");
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child.speak("Make me old man!");
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```
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The use of the word `extends` indicates that this class shouldn’t be
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directly based on the default [Object](20200826201605-objects) prototype
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but on some other class. This is called the superclass. The derived
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class is the subclass. The superclass's constructor and methods can be
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called by appending `super` in front.
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