2018-10-10 18:03:03 -04:00
										 
									 
								 
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								id: 587d7db6367417b2b2512b9a
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											2020-12-16 00:37:30 -07:00
										 
									 
								 
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								title: 匹配出现零次或多次的字符
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											2018-10-10 18:03:03 -04:00
										 
									 
								 
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								challengeType: 1
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											2020-08-04 15:14:01 +08:00
										 
									 
								 
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								forumTopicId: 301351
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											2018-10-10 18:03:03 -04:00
										 
									 
								 
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								---
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											2020-12-16 00:37:30 -07:00
										 
									 
								 
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								# --description--
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								上一次的挑战中使用了加号`+`来查找出现一次或多次的字符。还有一个选项可以匹配出现零次或多次的字符。
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								执行该操作的字符叫做`asterisk`或`star`,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); // Returns ["goooooooo"]
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								gPhrase.match(goRegex); // Returns ["g"]
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								oPhrase.match(goRegex); // Returns null
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								```
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											2020-12-16 00:37:30 -07:00
										 
									 
								 
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								# --instructions--
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								在这个挑战里,`chewieQuote` 已经被初始化为 "Aaaaaaaaaaaaaaaarrrgh!"。创建一个变量为`chewieRegex`的正则表达式,使用`*`符号在`chewieQuote`中匹配`"A"`及其之后出现的零个或多个`"a"`。你的正则表达式不需要使用修饰符,也不需要匹配引号。
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								# --hints--
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								你的正则表达式`chewieRegex`应该使用`*`符号匹配`'A'`之后出现的零个或多个`'a'`字符。
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								```js
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								assert(/\*/.test(chewieRegex.source));
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								```
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								正则表达式应当匹配 `chewieQuote` 里的 `"A"`。
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								```js
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								assert(result[0][0] === 'A');
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								```
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								你的正则表达式应该匹配`'Aaaaaaaaaaaaaaaa'`。
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								```js
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								assert(result[0] === 'Aaaaaaaaaaaaaaaa');
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								```
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								你的正则表达式`chewieRegex`应该匹配 16 个字符。
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								```js
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								assert(result[0].length === 16);
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								```
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								你的正则表达式在`'He made a fair move. Screaming about it can't help you.'`中不应该匹配任何字符。
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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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								你的正则表达式在`'Let him have it. It's not wise to upset a Wookiee.'`中不应该匹配任何字符。
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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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								# --solutions--
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