79 lines
2.0 KiB
Markdown
79 lines
2.0 KiB
Markdown
---
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id: 56bbb991ad1ed5201cd392cd
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title: Manipulate Arrays With shift()
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localeTitle: Manipular matrices con cambio ()
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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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<code>pop()</code> siempre elimina el último elemento de una matriz. ¿Qué pasa si quieres eliminar el primero?
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Ahí es donde <code>.shift()</code> en <code>.shift()</code> . Funciona igual que <code>.pop()</code> , excepto que elimina el primer elemento en lugar del último.
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</section>
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## Instructions
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<section id='instructions'>
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Use la función <code>.shift()</code> para eliminar el primer elemento de <code>myArray</code> , asignando el valor "desviado" a <code>removedFromMyArray</code> .
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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>myArray</code> ahora debe ser igual a <code>[["dog", 3]]</code> .'
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testString: 'assert((function(d){if(d[0][0] == "dog" && d[0][1] === 3 && d[1] == undefined){return true;}else{return false;}})(myArray), "<code>myArray</code> should now equal <code>[["dog", 3]]</code>.");'
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- text: ' <code>removedFromMyArray</code> debe contener <code>["John", 23]</code> .'
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testString: 'assert((function(d){if(d[0] == "John" && d[1] === 23 && typeof removedFromMyArray === "object"){return true;}else{return false;}})(removedFromMyArray), "<code>removedFromMyArray</code> should contain <code>["John", 23]</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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// Example
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var ourArray = ["Stimpson", "J", ["cat"]];
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var removedFromOurArray = ourArray.shift();
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// removedFromOurArray now equals "Stimpson" and ourArray now equals ["J", ["cat"]].
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// Setup
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var myArray = [["John", 23], ["dog", 3]];
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// Only change code below this line.
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var removedFromMyArray;
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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console.info('after the test');
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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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var myArray = [["John", 23], ["dog", 3]];
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// Only change code below this line.
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var removedFromMyArray = myArray.shift();
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```
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</section>
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