91 lines
1.8 KiB
Markdown
91 lines
1.8 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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forumTopicId: 301365
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dashedName: specify-exact-number-of-matches
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---
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# --description--
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You can specify the lower and upper number of patterns with quantity specifiers 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 `"hah"` with the letter `a` `3` times, your regex would be `/ha{3}h/`.
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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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# --instructions--
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Change the regex `timRegex` to match the word `"Timber"` only when it has four letter `m`'s.
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# --hints--
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Your regex should use curly brackets.
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```js
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assert(timRegex.source.match(/{.*?}/).length > 0);
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```
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Your regex should not match `"Timber"`
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```js
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timRegex.lastIndex = 0;
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assert(!timRegex.test('Timber'));
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```
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Your regex should not match `"Timmber"`
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```js
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timRegex.lastIndex = 0;
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assert(!timRegex.test('Timmber'));
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```
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Your regex should not match `"Timmmber"`
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```js
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timRegex.lastIndex = 0;
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assert(!timRegex.test('Timmmber'));
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```
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Your regex should match `"Timmmmber"`
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```js
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timRegex.lastIndex = 0;
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assert(timRegex.test('Timmmmber'));
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```
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Your regex should not match `"Timber"` with 30 `m`'s in it.
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```js
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timRegex.lastIndex = 0;
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assert(!timRegex.test('Ti' + 'm'.repeat(30) + 'ber'));
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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 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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# --solutions--
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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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