73 lines
		
	
	
		
			7.2 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			73 lines
		
	
	
		
			7.2 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								---
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								id: a10d2431ad0c6a099a4b8b52
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								title: Everything Be True
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								isRequired: true
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								challengeType: 5
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								videoUrl: ''
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								localeTitle: Все верно
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								---
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								## Description
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								<section id="description"> Проверьте, является ли предикат (второй аргумент) <dfn>правдивым</dfn> для всех элементов коллекции (первый аргумент). Другими словами, вам предоставляется массив объектов. Предикат <code>pre</code> будет свойством объекта, и вам нужно вернуть <code>true</code> если его значение является <code>truthy</code> . В противном случае верните <code>false</code> . В JavaScript <code>truthy</code> значениями являются значения, которые переводятся в <code>true</code> при оценке в булевом контексте. Помните, что вы можете получить доступ к свойствам объекта с помощью либо точечной нотации, либо обозначения <code>[]</code> . Не забудьте использовать <a href="http://forum.freecodecamp.org/t/how-to-get-help-when-you-are-stuck/19514" target="_blank">Read-Search-Ask,</a> если вы застряли. Попробуйте подключить программу. Напишите свой собственный код. </section>
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								## Instructions
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								<section id="instructions">
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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>truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex")</code> должны верны.'
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								    testString: 'assert.strictEqual(truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex"), true, "<code>truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex")</code> should return true.");'
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								  - text: '<code>truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex")</code> должен возвращать false.'
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								    testString: 'assert.strictEqual(truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex"), false, "<code>truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex")</code> should return false.");'
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								  - text: '<code>truthCheck([{"user": "Tinky-Winky", "sex": "male", "age": 0}, {"user": "Dipsy", "sex": "male", "age": 3}, {"user": "Laa-Laa", "sex": "female", "age": 5}, {"user": "Po", "sex": "female", "age": 4}], "age")</code> должен возвращать значение false.'
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								    testString: 'assert.strictEqual(truthCheck([{"user": "Tinky-Winky", "sex": "male", "age": 2}, {"user": "Dipsy", "sex": "male", "age": 0}, {"user": "Laa-Laa", "sex": "female", "age": 5}, {"user": "Po", "sex": "female", "age": 4}], "age"), false, "<code>truthCheck([{"user": "Tinky-Winky", "sex": "male", "age": 0}, {"user": "Dipsy", "sex": "male", "age": 3}, {"user": "Laa-Laa", "sex": "female", "age": 5}, {"user": "Po", "sex": "female", "age": 4}], "age")</code> should return false.");'
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								  - text: '<code>truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true}, {"name": "FastFoward", "onBoat": null}], "onBoat")</code> должен возвращать false'
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								    testString: 'assert.strictEqual(truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true}, {"name": "FastFoward", "onBoat": null}], "onBoat"), false, "<code>truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true}, {"name": "FastFoward", "onBoat": null}], "onBoat")</code> should return false");'
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								  - text: '<code>truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true, "alias": "Repete"}, {"name": "FastFoward", "onBoat": true}], "onBoat")</code> должен возвращать true'
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								    testString: 'assert.strictEqual(truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true, "alias": "Repete"}, {"name": "FastFoward", "onBoat": true}], "onBoat"), true, "<code>truthCheck([{"name": "Pete", "onBoat": true}, {"name": "Repeat", "onBoat": true, "alias": "Repete"}, {"name": "FastFoward", "onBoat": true}], "onBoat")</code> should return true");'
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								  - text: '<code>truthCheck([{"single": "yes"}], "single")</code> должен возвращать true'
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								    testString: 'assert.strictEqual(truthCheck([{"single": "yes"}], "single"), true, "<code>truthCheck([{"single": "yes"}], "single")</code> should return true");'
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								  - text: '<code>truthCheck([{"single": ""}, {"single": "double"}], "single")</code> должен возвращать false'
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								    testString: 'assert.strictEqual(truthCheck([{"single": ""}, {"single": "double"}], "single"), false, "<code>truthCheck([{"single": ""}, {"single": "double"}], "single")</code> should return false");'
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								  - text: '<code>truthCheck([{"single": "double"}, {"single": undefined}], "single")</code> должен возвращать false'
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								    testString: 'assert.strictEqual(truthCheck([{"single": "double"}, {"single": undefined}], "single"), false, "<code>truthCheck([{"single": "double"}, {"single": undefined}], "single")</code> should return false");'
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								  - text: '<code>truthCheck([{"single": "double"}, {"single": NaN}], "single")</code> должен возвращать false'
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								    testString: 'assert.strictEqual(truthCheck([{"single": "double"}, {"single": NaN}], "single"), false, "<code>truthCheck([{"single": "double"}, {"single": NaN}], "single")</code> should return false");'
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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 truthCheck(collection, pre) {
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								  // Is everyone being true?
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								  return pre;
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								}
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								truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex");
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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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