74 lines
2.5 KiB
Markdown
74 lines
2.5 KiB
Markdown
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---
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id: 587d7b8c367417b2b2512b55
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title: Share Javascript Code Using import
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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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In the past, <code>require()</code> was used to add things from external files. While handy, this presents a problem: some files are rather large and you may only need certain parts of those external resources.
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ES6 gives you a very handy tool known as <code>import</code>. With it, you can choose which parts of a file or module to load, saving time and memory.
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Imagine a file that has 20 functions, but you only need to use one of those functions. <code>require()</code> would force you to bring in all 20 functions. With the <code>import</code> syntax, you can bring in just the one you need, like so:
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<blockquote>import { desired_function } from './other_file';</blockquote>
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Here, <code>import</code> will find <code>desired_function</code> in <code>other_file</code>, import just that function for you to use, and ignore the rest. The <code>./</code> tells the import to look for the <code>other_file</code> in the same folder that the file which uses the import statement is in. The whitespace around the function inside the curly braces is best practice for readability.
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You can import multiple items like this:
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<blockquote>import { item1, item2 } from './other_file';</blockquote>
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There are a few ways to write an <code>import</code> statement, but the above are a very common use-case.
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</section>
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## Instructions
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<section id='instructions'>
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Add the appropriate <code>import</code> statement that will allow the current file to use the <code>capitalizeString</code> function. The file where this function lives is called <code>string_functions</code>, and it is in the same directory as the current file.
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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: Use a valid <code>import</code> statement
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testString: getUserInput => assert(getUserInput('index').match(/import\s*\{\s*capitalizeString\s*\}\s*from\s*("|')(\.\/string_functions|string_functions)\1(|\/\/|;\s|\s)/g));
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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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"use strict";
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capitalizeString("hello!");
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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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self.require = function (str) {
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if (str === 'string_functions') {
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return {
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capitalizeString: str => str.toUpperCase()
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}
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}
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};
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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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import { capitalizeString } from './string_functions';
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capitalizeString("hello!");
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```
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</section>
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