75 lines
2.0 KiB
Markdown
75 lines
2.0 KiB
Markdown
---
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id: 587d7db5367417b2b2512b96
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title: Match Letters of the Alphabet
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challengeType: 1
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forumTopicId: 301354
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---
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## Description
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<section id='description'>
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You saw how you can use <dfn>character sets</dfn> to specify a group of characters to match, but that's a lot of typing when you need to match a large range of characters (for example, every letter in the alphabet). Fortunately, there is a built-in feature that makes this short and simple.
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Inside a character set, you can define a range of characters to match using a hyphen character: <code>-</code>.
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For example, to match lowercase letters <code>a</code> through <code>e</code> you would use <code>[a-e]</code>.
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```js
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let catStr = "cat";
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let batStr = "bat";
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let matStr = "mat";
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let bgRegex = /[a-e]at/;
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catStr.match(bgRegex); // Returns ["cat"]
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batStr.match(bgRegex); // Returns ["bat"]
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matStr.match(bgRegex); // Returns null
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```
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</section>
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## Instructions
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<section id='instructions'>
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Match all the letters in the string <code>quoteSample</code>.
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<strong>Note</strong><br>Be sure to match both upper- and lowercase <strong>letters<strong>.
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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: Your regex <code>alphabetRegex</code> should match 35 items.
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testString: assert(result.length == 35);
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- text: Your regex <code>alphabetRegex</code> should use the global flag.
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testString: assert(alphabetRegex.flags.match(/g/).length == 1);
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- text: Your regex <code>alphabetRegex</code> should use the case insensitive flag.
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testString: assert(alphabetRegex.flags.match(/i/).length == 1);
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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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let quoteSample = "The quick brown fox jumps over the lazy dog.";
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let alphabetRegex = /change/; // Change this line
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let result = alphabetRegex; // Change this line
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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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let quoteSample = "The quick brown fox jumps over the lazy dog.";
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let alphabetRegex = /[a-z]/gi; // Change this line
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let result = quoteSample.match(alphabetRegex); // Change this line
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```
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</section>
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