79 lines
2.1 KiB
Markdown
79 lines
2.1 KiB
Markdown
---
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id: 587d7db9367417b2b2512ba7
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title: Specify Exact Number of Matches
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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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You can specify the lower and upper number of patterns with <code>quantity specifiers</code> using curly brackets. Sometimes you only want a specific number of matches.
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To specify a certain number of patterns, just have that one number between the curly brackets.
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For example, to match only the word <code>"hah"</code> with the letter <code>a</code> <code>3</code> times, your regex would be <code>/ha{3}h/</code>.
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```js
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let A4 = "haaaah";
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let A3 = "haaah";
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let A100 = "h" + "a".repeat(100) + "h";
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let multipleHA = /ha{3}h/;
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multipleHA.test(A4); // Returns false
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multipleHA.test(A3); // Returns true
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multipleHA.test(A100); // Returns false
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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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Change the regex <code>timRegex</code> to match the word <code>"Timber"</code> only when it has four letter <code>m</code>'s.
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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 curly brackets.
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testString: assert(timRegex.source.match(/{.*?}/).length > 0);
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- text: Your regex should not match <code>"Timber"</code>
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testString: assert(!timRegex.test("Timber"));
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- text: Your regex should not match <code>"Timmber"</code>
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testString: assert(!timRegex.test("Timmber"));
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- text: Your regex should not match <code>"Timmmber"</code>
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testString: assert(!timRegex.test("Timmmber"));
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- text: Your regex should match <code>"Timmmmber"</code>
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testString: assert(timRegex.test("Timmmmber"));
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- text: Your regex should not match <code>"Timber"</code> with 30 <code>m</code>'s in it.
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testString: assert(!timRegex.test("Ti" + "m".repeat(30) + "ber"));
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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 timStr = "Timmmmber";
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let timRegex = /change/; // Change this line
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let result = timRegex.test(timStr);
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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 timStr = "Timmmmber";
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let timRegex = /Tim{4}ber/; // Change this line
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let result = timRegex.test(timStr);
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```
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</section>
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