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>
85 lines
2.4 KiB
Markdown
85 lines
2.4 KiB
Markdown
---
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id: 587d7db5367417b2b2512b95
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title: Match Single Character with Multiple Possibilities
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challengeType: 1
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forumTopicId: 301357
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dashedName: match-single-character-with-multiple-possibilities
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---
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# --description--
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You learned how to match literal patterns (`/literal/`) and wildcard character (`/./`). Those are the extremes of regular expressions, where one finds exact matches and the other matches everything. There are options that are a balance between the two extremes.
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You can search for a literal pattern with some flexibility with <dfn>character classes</dfn>. Character classes allow you to define a group of characters you wish to match by placing them inside square (`[` and `]`) brackets.
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For example, you want to match `"bag"`, `"big"`, and `"bug"` but not `"bog"`. You can create the regex `/b[aiu]g/` to do this. The `[aiu]` is the character class that will only match the characters `"a"`, `"i"`, or `"u"`.
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```js
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let bigStr = "big";
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let bagStr = "bag";
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let bugStr = "bug";
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let bogStr = "bog";
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let bgRegex = /b[aiu]g/;
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bigStr.match(bgRegex); // Returns ["big"]
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bagStr.match(bgRegex); // Returns ["bag"]
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bugStr.match(bgRegex); // Returns ["bug"]
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bogStr.match(bgRegex); // Returns null
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```
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# --instructions--
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Use a character class with vowels (`a`, `e`, `i`, `o`, `u`) in your regex `vowelRegex` to find all the vowels in the string `quoteSample`.
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**Note**
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Be sure to match both upper- and lowercase vowels.
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# --hints--
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You should find all 25 vowels.
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```js
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assert(result.length == 25);
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```
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Your regex `vowelRegex` should use a character class.
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```js
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assert(/\[.*\]/.test(vowelRegex.source));
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```
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Your regex `vowelRegex` should use the global flag.
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```js
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assert(vowelRegex.flags.match(/g/).length == 1);
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```
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Your regex `vowelRegex` should use the case insensitive flag.
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```js
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assert(vowelRegex.flags.match(/i/).length == 1);
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```
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Your regex should not match any consonants.
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```js
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assert(!/[b-df-hj-np-tv-z]/gi.test(result.join()));
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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 = "Beware of bugs in the above code; I have only proved it correct, not tried it.";
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let vowelRegex = /change/; // Change this line
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let result = vowelRegex; // Change this line
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```
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# --solutions--
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```js
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let quoteSample = "Beware of bugs in the above code; I have only proved it correct, not tried it.";
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let vowelRegex = /[aeiou]/gi; // Change this line
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let result = quoteSample.match(vowelRegex); // Change this line
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```
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