68 lines
2.2 KiB
Markdown
68 lines
2.2 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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challengeType: 1
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videoUrl: ''
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localeTitle: Сбросить свойство унаследованного конструктора
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---
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## Description
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<section id="description"> Когда объект наследует свой <code>prototype</code> от другого объекта, он также наследует свойство конструктора <code>supertype</code> . Вот пример: <blockquote> function Bird () {} <br> Bird.prototype = Object.create (Animal.prototype); <br> let duck = new Bird (); <br> duck.constructor // function Animal () {...} </blockquote> Но <code>duck</code> и все случаи <code>Bird</code> должны показать, что они были построены <code>Bird</code> а не <code>Animal</code> . Для этого, вы можете вручную установить <code>Bird's</code> свойство конструктора для <code>Bird</code> объекта: <blockquote> Bird.prototype.constructor = Bird; <br> duck.constructor // function Bird () {...} </blockquote></section>
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## Instructions
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undefined
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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: ''
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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: ''
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testString: 'assert(duck.constructor === Bird, "<code>duck.constructor</code> should return <code>Bird</code>.");'
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- text: ''
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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: ''
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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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// solution required
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```
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</section>
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