84 lines
2.7 KiB
Markdown
84 lines
2.7 KiB
Markdown
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---
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id: 587d7db1367417b2b2512b86
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title: Reset an Inherited Constructor Property
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localeTitle: Restablecer una propiedad de constructor heredada
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challengeType: 1
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---
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## Description
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<section id='description'>
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Cuando un objeto hereda su <code>prototype</code> de otro objeto, sino que también hereda el <code>supertype</code> propiedad constructor 's.
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Aquí hay un ejemplo:
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<blockquote>function Bird() { }<br>Bird.prototype = Object.create(Animal.prototype);<br>let duck = new Bird();<br>duck.constructor // function Animal(){...}</blockquote>
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Pero el <code>duck</code> y todos los casos de <code>Bird</code> deben mostrar que fueron construidos por <code>Bird</code> y no por <code>Animal</code> . Para hacerlo, puedes establecer manualmente <code>Bird's</code> propiedad <code>Bird's</code> constructor de <code>Bird</code> objeto <code>Bird</code> :
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<blockquote>Bird.prototype.constructor = Bird;<br>duck.constructor // function Bird(){...}</blockquote>
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</section>
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## Instructions
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<section id='instructions'>
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<code>duck.constructor</code> el código para que <code>duck.constructor</code> y <code>beagle.constructor</code> devuelvan sus respectivos constructores.
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>Bird.prototype</code> debe ser una instancia de <code>Animal</code> .
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testString: 'assert(Animal.prototype.isPrototypeOf(Bird.prototype), "<code>Bird.prototype</code> should be an instance of <code>Animal</code>.");'
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- text: <code>duck.constructor</code> debe devolver <code>Bird</code> .
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testString: 'assert(duck.constructor === Bird, "<code>duck.constructor</code> should return <code>Bird</code>.");'
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- text: <code>Dog.prototype</code> debe ser una instancia de <code>Animal</code> .
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testString: 'assert(Animal.prototype.isPrototypeOf(Dog.prototype), "<code>Dog.prototype</code> should be an instance of <code>Animal</code>.");'
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- text: <code>beagle.constructor</code> debe devolver el <code>Dog</code> .
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testString: 'assert(beagle.constructor === Dog, "<code>beagle.constructor</code> should return <code>Dog</code>.");'
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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function Animal() { }
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function Bird() { }
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function Dog() { }
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Bird.prototype = Object.create(Animal.prototype);
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Dog.prototype = Object.create(Animal.prototype);
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// Add your code below this line
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let duck = new Bird();
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let beagle = new Dog();
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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function Animal() { }
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function Bird() { }
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function Dog() { }
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Bird.prototype = Object.create(Animal.prototype);
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Dog.prototype = Object.create(Animal.prototype);
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Dog.prototype.constructor = Dog;
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Bird.prototype.constructor = Bird;
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let duck = new Bird();
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let beagle = new Dog();
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```
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</section>
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