2024-05-06 20:40:05 +00:00
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---
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2024-10-30 17:04:36 +00:00
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date: 20201113
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2024-05-06 20:40:05 +00:00
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id: fd03be0e-a4c0-421f-9dd7-1bddc9dece65
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title: JavaScript Prototypes
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---
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# Description
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A prototype can be seen as an [object](20200826201605-objects) another
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object extends.
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# Syntax
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``` javascript
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let protoRabbit = {
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speak(line) {
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console.log(`The ${this.type} rabbit says '${line}'`); // : The killer rabbit says 'SKREEEE!'
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},
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};
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let killerRabbit = Object.create(protoRabbit);
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killerRabbit.type = "killer";
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killerRabbit.speak("SKREEEE!");
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```
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# Object.prototype
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Most objects in JavaScript eventually extend `Object.prototype` through
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parent prototype objects or directly, which provides a bunch of default
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methods[^1].
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``` javascript
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console.log(Object.getPrototypeOf({}) == Object.prototype); // true
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console.log(Object.getPrototypeOf(Object.prototype)); // null
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```
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# Footnotes
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[^1]: <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object>
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