112 lines
2.4 KiB
Markdown
112 lines
2.4 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244bf
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title: Local Scope and Functions
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localeTitle: Ámbito local y funciones
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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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Las variables que se declaran dentro de una función, así como los parámetros de la función tienen alcance <dfn>local</dfn> . Eso significa que, sólo son visibles dentro de esa función.
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Aquí hay una función <code>myTest</code> con una variable local llamada <code>loc</code> .
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<blockquote>function myTest() {<br> var loc = "foo";<br> console.log(loc);<br>}<br>myTest(); // logs "foo"<br>console.log(loc); // loc is not defined</blockquote>
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<code>loc</code> no está definido fuera de la función.
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</section>
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## Instructions
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<section id='instructions'>
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Declare una variable local <code>myVar</code> dentro de <code>myLocalScope</code> . Ejecute las pruebas y luego siga las instrucciones comentadas en el editor.
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<strong>Pista</strong> <br> Actualizar la página puede ayudar si te quedas atascado.
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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: Ninguna variable global <code>myVar</code>
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testString: 'assert(typeof myVar === "undefined", "No global <code>myVar</code> variable");'
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- text: Agrega una variable <code>myVar</code> local
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testString: 'assert(/var\s+myVar/.test(code), "Add a local <code>myVar</code> variable");'
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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 myLocalScope() {
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'use strict'; // you shouldn't need to edit this line
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console.log(myVar);
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}
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myLocalScope();
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// Run and check the console
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// myVar is not defined outside of myLocalScope
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console.log(myVar);
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// Now remove the console log line to pass the test
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```
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</div>
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### Before Test
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<div id='js-setup'>
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```js
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var logOutput = "";
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var originalConsole = console
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function capture() {
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var nativeLog = console.log;
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console.log = function (message) {
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logOutput = message;
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if(nativeLog.apply) {
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nativeLog.apply(originalConsole, arguments);
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} else {
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var nativeMsg = Array.prototype.slice.apply(arguments).join(' ');
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nativeLog(nativeMsg);
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}
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};
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}
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function uncapture() {
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console.log = originalConsole.log;
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}
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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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function myLocalScope() {
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'use strict';
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var myVar;
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console.log(myVar);
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}
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myLocalScope();
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```
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</section>
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