ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
97 lines
2.6 KiB
Markdown
97 lines
2.6 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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dashedName: match-all-letters-and-numbers
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---
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# --description--
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Using character classes, you were able to search for all letters of the alphabet with `[a-z]`. 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 `\w`. This shortcut is equal to `[A-Za-z0-9_]`. This character class matches upper and lowercase letters plus numbers. Note, this character class also includes the underscore character (`_`).
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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 <dfn>shorthand character classes</dfn>.
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# --instructions--
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Use the shorthand character class `\w` to count the number of alphanumeric characters in various quotes and strings.
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# --hints--
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Your regex should use the global flag.
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```js
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assert(alphabetRegexV2.global);
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```
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Your regex should use the shorthand character `\w` to match all characters which are alphanumeric.
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```js
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assert(/\\w/.test(alphabetRegexV2.source));
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```
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Your regex should find 31 alphanumeric characters in `"The five boxing wizards jump quickly."`
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```js
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assert(
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'The five boxing wizards jump quickly.'.match(alphabetRegexV2).length === 31
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);
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```
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Your regex should find 32 alphanumeric characters in `"Pack my box with five dozen liquor jugs."`
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```js
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assert(
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'Pack my box with five dozen liquor jugs.'.match(alphabetRegexV2).length ===
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32
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);
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```
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Your regex should find 30 alphanumeric characters in `"How vexingly quick daft zebras jump!"`
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```js
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assert(
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'How vexingly quick daft zebras jump!'.match(alphabetRegexV2).length === 30
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);
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```
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Your regex should find 36 alphanumeric characters in `"123 456 7890 ABC def GHI jkl MNO pqr STU vwx YZ."`
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```js
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assert(
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'123 456 7890 ABC def GHI jkl MNO pqr STU vwx YZ.'.match(alphabetRegexV2)
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.length === 36
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);
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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 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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# --solutions--
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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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