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97 lines
2.2 KiB
Markdown
97 lines
2.2 KiB
Markdown
---
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id: 56bbb991ad1ed5201cd392cf
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title: Write Reusable JavaScript with Functions
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challengeType: 1
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forumTopicId: 18378
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dashedName: write-reusable-javascript-with-functions
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---
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# --description--
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In JavaScript, we can divide up our code into reusable parts called <dfn>functions</dfn>.
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Here's an example of a function:
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```js
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function functionName() {
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console.log("Hello World");
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}
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```
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You can call or <dfn>invoke</dfn> this function by using its name followed by parentheses, like this: `functionName();` Each time the function is called it will print out the message `Hello World` on the dev console. All of the code between the curly braces will be executed every time the function is called.
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# --instructions--
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<ol>
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<li>
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Create a function called <code>reusableFunction</code> which prints the string <code>Hi World</code> to the dev console.
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</li>
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<li>
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Call the function.
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</li>
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</ol>
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# --before-each--
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```js
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function testConsole() {
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var originalConsole = console;
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var nativeLog = console.log;
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var hiWorldWasLogged = false;
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console.log = function (message) {
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if (message === 'Hi World') {
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console.warn(message);
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hiWorldWasLogged = true;
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}
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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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reusableFunction();
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console.log = nativeLog;
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return hiWorldWasLogged;
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}
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```
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# --hints--
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`reusableFunction` should be a function.
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```js
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assert(typeof reusableFunction === 'function');
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```
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If `reusableFunction` is called, it should output the string `Hi World` to the console.
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```js
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assert(testConsole());
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```
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You should call `reusableFunction` once it is defined.
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```js
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const functionStr = reusableFunction && __helpers.removeWhiteSpace(reusableFunction.toString());
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const codeWithoutFunction = __helpers.removeWhiteSpace(__helpers.removeJSComments(code)).replace(/reusableFunction\(\)\{/g, '');
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assert(/reusableFunction\(\)/.test(codeWithoutFunction));
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```
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# --seed--
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## --seed-contents--
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```js
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```
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# --solutions--
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```js
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function reusableFunction() {
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console.log("Hi World");
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}
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reusableFunction();
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```
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