102 lines
2.2 KiB
Markdown
102 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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videoUrl: 'https://scrimba.com/c/cL6dqfy'
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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><li>Create a function called <code>reusableFunction</code> which prints <code>"Hi World"</code> to the dev console.</li><li>Call the function.</li></ol>
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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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`reusableFunction` should output "Hi World" to the dev console.
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```js
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assert(hiWorldWasLogged);
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```
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You should call `reusableFunction` after you define it.
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```js
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assert(/^\s*reusableFunction\(\)\s*/m.test(code));
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```
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# --seed--
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## --before-user-code--
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```js
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var logOutput = "";
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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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function capture() {
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console.log = function (message) {
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if(message === 'Hi World') hiWorldWasLogged = true;
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if(message && message.trim) logOutput = message.trim();
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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 = nativeLog;
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}
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capture();
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```
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## --after-user-code--
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```js
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uncapture();
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if (typeof reusableFunction !== "function") {
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(function() { return "reusableFunction is not defined"; })();
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} else {
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(function() { return logOutput || "console.log never called"; })();
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}
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```
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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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