83 lines
6.8 KiB
Markdown
83 lines
6.8 KiB
Markdown
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---
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id: a10d2431ad0c6a099a4b8b52
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title: Everything Be True
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localeTitle: Todo sea verdad
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isRequired: true
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challengeType: 5
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---
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## Description
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<section id='description'>
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Compruebe si el predicado (segundo argumento) es <dfn>verdadero</dfn> en todos los elementos de una colección (primer argumento).
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En otras palabras, se le da una colección de objetos de matriz. El predicado <code>pre</code> será una propiedad de objeto y debe devolver <code>true</code> si su valor es <code>truthy</code> . De lo contrario, devuelve <code>false</code> .
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En JavaScript, los valores de <code>truthy</code> son valores que se convierten en <code>true</code> cuando se evalúan en un contexto booleano.
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Recuerde, puede acceder a las propiedades del objeto a través de la notación de puntos o la notación de <code>[]</code> .
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Recuerda usar <a href='http://forum.freecodecamp.org/t/how-to-get-help-when-you-are-stuck/19514' target='_blank'>Read-Search-Ask</a> si te atascas. Trate de emparejar el programa. Escribe tu propio código.
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</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> debe devolver el valor".
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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> debe devolver falso.
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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> debe devolver falso.
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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> debe devolver falso '
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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> debe devolver 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> debe devolver verdadero'
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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> debe devolver falso'
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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> debe devolver falso'
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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> debe devolver falso'
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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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function truthCheck(collection, pre) {
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// Does everyone have one of these?
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return collection.every(function(e) { return e[pre]; });
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}
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```
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</section>
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