133 lines
3.5 KiB
Markdown
133 lines
3.5 KiB
Markdown
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---
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id: 56533eb9ac21ba0edf2244be
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title: Global Scope and Functions
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localeTitle: Ámbito global 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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En JavaScript, el <dfn>alcance se</dfn> refiere a la visibilidad de las variables. Las variables que se definen fuera de un bloque de función tienen alcance <dfn>global</dfn> . Esto significa que pueden verse en todas partes en su código JavaScript.
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Las variables que se utilizan sin la palabra clave <code>var</code> se crean automáticamente en el ámbito <code>global</code> . Esto puede crear consecuencias no deseadas en otra parte de su código o al ejecutar una función nuevamente. Siempre debes declarar tus variables con <code>var</code> .
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</section>
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## Instructions
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<section id='instructions'>
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Usando <code>var</code> , declare una variable <code>global</code> <code>myGlobal</code> fuera de cualquier función. Inicialízalo con un valor de <code>10</code> .
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Dentro de la función <code>fun1</code> , asigne <code>5</code> a <code>oopsGlobal</code> <strong><em>sin</em></strong> usar la palabra clave <code>var</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>myGlobal</code> debe ser definido
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testString: 'assert(typeof myGlobal != "undefined", "<code>myGlobal</code> should be defined");'
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- text: <code>myGlobal</code> debe tener un valor de <code>10</code>
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testString: 'assert(myGlobal === 10, "<code>myGlobal</code> should have a value of <code>10</code>");'
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- text: <code>myGlobal</code> debe declararse usando la palabra clave <code>var</code>
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testString: 'assert(/var\s+myGlobal/.test(code), "<code>myGlobal</code> should be declared using the <code>var</code> keyword");'
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- text: <code>oopsGlobal</code> debe ser una variable global y tener un valor de <code>5</code>
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testString: 'assert(typeof oopsGlobal != "undefined" && oopsGlobal === 5, "<code>oopsGlobal</code> should be a global variable and have a value of <code>5</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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// Declare your variable here
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function fun1() {
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// Assign 5 to oopsGlobal Here
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}
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// Only change code above this line
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function fun2() {
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var output = "";
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if (typeof myGlobal != "undefined") {
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output += "myGlobal: " + myGlobal;
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}
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if (typeof oopsGlobal != "undefined") {
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output += " oopsGlobal: " + oopsGlobal;
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}
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console.log(output);
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}
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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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var oopsGlobal;
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capture();
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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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// Declare your variable here
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var myGlobal = 10;
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function fun1() {
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// Assign 5 to oopsGlobal Here
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oopsGlobal = 5;
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}
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// Only change code above this line
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function fun2() {
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var output = "";
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if(typeof myGlobal != "undefined") {
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output += "myGlobal: " + myGlobal;
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}
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if(typeof oopsGlobal != "undefined") {
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output += " oopsGlobal: " + oopsGlobal;
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}
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console.log(output);
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}
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```
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</section>
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