81 lines
2.9 KiB
Markdown
81 lines
2.9 KiB
Markdown
---
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id: 587d7db7367417b2b2512b9f
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title: Match All Letters and Numbers
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challengeType: 1
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forumTopicId: 301346
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---
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## Description
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<section id='description'>
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Using character classes, you were able to search for all letters of the alphabet with <code>[a-z]</code>. This kind of character class is common enough that there is a shortcut for it, although it includes a few extra characters as well.
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The closest character class in JavaScript to match the alphabet is <code>\w</code>. This shortcut is equal to <code>[A-Za-z0-9_]</code>. This character class matches upper and lowercase letters plus numbers. Note, this character class also includes the underscore character (<code>_</code>).
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```js
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let longHand = /[A-Za-z0-9_]+/;
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let shortHand = /\w+/;
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let numbers = "42";
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let varNames = "important_var";
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longHand.test(numbers); // Returns true
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shortHand.test(numbers); // Returns true
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longHand.test(varNames); // Returns true
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shortHand.test(varNames); // Returns true
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```
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These shortcut character classes are also known as <code>shorthand character classes</code>.
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</section>
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## Instructions
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<section id='instructions'>
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Use the shorthand character class <code>\w</code> to count the number of alphanumeric characters in various quotes and strings.
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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 should use the global flag.
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testString: assert(alphabetRegexV2.global);
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- text: Your regex should use the shorthand character <code>\w</code> to match all characters which are alphanumeric.
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testString: assert(/\\w/.test(alphabetRegexV2.source));
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- text: Your regex should find 31 alphanumeric characters in <code>"The five boxing wizards jump quickly."</code>
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testString: assert("The five boxing wizards jump quickly.".match(alphabetRegexV2).length === 31);
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- text: Your regex should find 32 alphanumeric characters in <code>"Pack my box with five dozen liquor jugs."</code>
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testString: assert("Pack my box with five dozen liquor jugs.".match(alphabetRegexV2).length === 32);
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- text: Your regex should find 30 alphanumeric characters in <code>"How vexingly quick daft zebras jump!"</code>
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testString: assert("How vexingly quick daft zebras jump!".match(alphabetRegexV2).length === 30);
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- text: Your regex should find 36 alphanumeric characters in <code>"123 456 7890 ABC def GHI jkl MNO pqr STU vwx YZ."</code>
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testString: assert("123 456 7890 ABC def GHI jkl MNO pqr STU vwx YZ.".match(alphabetRegexV2).length === 36);
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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 five boxing wizards jump quickly.";
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let alphabetRegexV2 = /change/; // Change this line
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let result = quoteSample.match(alphabetRegexV2).length;
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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 five boxing wizards jump quickly.";
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let alphabetRegexV2 = /\w/g; // Change this line
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let result = quoteSample.match(alphabetRegexV2).length;
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```
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</section>
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