70 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			70 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								---
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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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								dashedName: match-letters-of-the-alphabet
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								---
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								# --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: `-`.
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								For example, to match lowercase letters `a` through `e` you would use `[a-e]`.
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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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								# --instructions--
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								Match all the letters in the string `quoteSample`.
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								**Note**: Be sure to match both uppercase and lowercase letters.
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								# --hints--
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								Your regex `alphabetRegex` should match 35 items.
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								```js
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								assert(result.length == 35);
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								```
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								Your regex `alphabetRegex` should use the global flag.
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								```js
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								assert(alphabetRegex.flags.match(/g/).length == 1);
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								```
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								Your regex `alphabetRegex` should use the case insensitive flag.
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								```js
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								assert(alphabetRegex.flags.match(/i/).length == 1);
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								```
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								# --seed--
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								## --seed-contents--
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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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								# --solutions--
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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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