97 lines
2.3 KiB
Markdown
97 lines
2.3 KiB
Markdown
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---
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id: 587d7db6367417b2b2512b9a
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title: 匹配出現零次或多次的字符
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challengeType: 1
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forumTopicId: 301351
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dashedName: match-characters-that-occur-zero-or-more-times
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---
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# --description--
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上一次的挑戰中使用了加號 `+` 來查找出現一次或多次的字符。 還有一個選項可以匹配出現零次或多次的字符。
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執行該操作的字符叫做星號，即`*`。
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```js
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let soccerWord = "gooooooooal!";
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let gPhrase = "gut feeling";
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let oPhrase = "over the moon";
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let goRegex = /go*/;
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soccerWord.match(goRegex);
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gPhrase.match(goRegex);
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oPhrase.match(goRegex);
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```
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按順序排列，三次 `match` 調用將返回值 `["goooooooo"]`，`["g"]` 和 `null`。
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# --instructions--
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在這個挑戰裏，`chewieQuote` 已經被初始化爲 `Aaaaaaaaaaaaaaaarrrgh!`。 創建一個變量爲 `chewieRegex` 的正則表達式，使用 `*` 在 `chewieQuote` 中匹配 `A` 及其之後出現的零個或多個`a`。 你的正則表達式不需要使用修飾符，也不需要匹配引號。
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# --hints--
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你的正則表達式 `chewieRegex` 應該使用 `*` 字符來匹配零或更多的 `a` 字符。
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```js
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assert(/\*/.test(chewieRegex.source));
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```
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正則表達式應當匹配 `chewieQuote` 裏的 `A`。
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```js
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assert(result[0][0] === 'A');
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```
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你的正則表達式應該與 `chewieQuote` 中的字符串 `Aaaaaaaaaaaaaaaa` 匹配。
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```js
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assert(result[0] === 'Aaaaaaaaaaaaaaaa');
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```
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你的正則表達式 `chewieRegex` 應該匹配 `chewieQuote` 中的 16 個字符。
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```js
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assert(result[0].length === 16);
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```
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你的正則表達式不應該有任何匹配，在字符 `He made a fair move. Screaming about it can't help you.`
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```js
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assert(
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!"He made a fair move. Screaming about it can't help you.".match(chewieRegex)
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);
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```
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你的正則表達式不應該有任何匹配，在字符 `Let him have it. It's not wise to upset a Wookiee.`
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```js
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assert(
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!"Let him have it. It's not wise to upset a Wookiee.".match(chewieRegex)
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);
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```
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# --seed--
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## --before-user-code--
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```js
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const chewieQuote = "Aaaaaaaaaaaaaaaarrrgh!";
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```
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## --seed-contents--
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```js
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// Only change code below this line
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let chewieRegex = /change/; // Change this line
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// Only change code above this line
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let result = chewieQuote.match(chewieRegex);
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```
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# --solutions--
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```js
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let chewieRegex = /Aa*/;
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let result = chewieQuote.match(chewieRegex);
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```
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