94 lines
2.1 KiB
Markdown
94 lines
2.1 KiB
Markdown
---
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id: 587d7db9367417b2b2512ba5
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title: Specify Upper and Lower Number of Matches
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challengeType: 1
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forumTopicId: 301367
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dashedName: specify-upper-and-lower-number-of-matches
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---
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# --description--
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Recall that you use the plus sign `+` to look for one or more characters and the asterisk `*` to look for zero or more characters. These are convenient but sometimes you want to match a certain range of patterns.
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You can specify the lower and upper number of patterns with <dfn>quantity specifiers</dfn>. Quantity specifiers are used with curly brackets (`{` and `}`). You put two numbers between the curly brackets - for the lower and upper number of patterns.
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For example, to match only the letter `a` appearing between `3` and `5` times in the string `ah`, your regex would be `/a{3,5}h/`.
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```js
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let A4 = "aaaah";
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let A2 = "aah";
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let multipleA = /a{3,5}h/;
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multipleA.test(A4);
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multipleA.test(A2);
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```
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The first `test` call would return `true`, while the second would return `false`.
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# --instructions--
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Change the regex `ohRegex` to match the entire phrase `Oh no` only when it has `3` to `6` letter `h`'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(ohRegex.source.match(/{.*?}/).length > 0);
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```
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Your regex should not match the string `Ohh no`
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```js
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ohRegex.lastIndex = 0;
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assert(!ohRegex.test('Ohh no'));
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```
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Your regex should match the string `Ohhh no`
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```js
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assert('Ohhh no'.match(ohRegex)[0].length === 7);
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```
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Your regex should match the string `Ohhhh no`
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```js
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assert('Ohhhh no'.match(ohRegex)[0].length === 8);
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```
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Your regex should match the string `Ohhhhh no`
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```js
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assert('Ohhhhh no'.match(ohRegex)[0].length === 9);
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```
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Your regex should match the string `Ohhhhhh no`
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```js
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assert('Ohhhhhh no'.match(ohRegex)[0].length === 10);
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```
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Your regex should not match the string `Ohhhhhhh no`
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```js
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ohRegex.lastIndex = 0;
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assert(!ohRegex.test('Ohhhhhhh no'));
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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 ohStr = "Ohhh no";
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let ohRegex = /change/; // Change this line
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let result = ohRegex.test(ohStr);
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```
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# --solutions--
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```js
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let ohStr = "Ohhh no";
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let ohRegex = /Oh{3,6} no/; // Change this line
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let result = ohRegex.test(ohStr);
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```
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