javascript -/g模式匹配的行为

Question

关于 this article , 它提到了

Make sure you are clear on the fact that an expression pattern is tested on each individual character. And that, just because the engine moves forward when following the pattern and looking for a match it still backtracks and examines each character in a string until a match is found or if the global flag is set until all characters are examined.

但是我用 Javascript 测试了什么

"aaa@bbb".match(/a+@b+/g)

不会产生如下结果:

["aaa@bbb", "aa@bbb", "a@bbb"]

它只产生["aaa@bbb"]。它似乎没有检查每个字符来测试模式。谁能解释一下匹配步骤？谢谢。

Answer 1

/g 并不意味着它会尝试查找输入字符串中可能与给定模式匹配的所有可能 字符子集。这意味着一旦找到匹配项，它将继续搜索更多可能匹配从上一个匹配项开始的模式的子字符串。

例如:

"aaa@bbb ... aaaa@bbbb".match(/a+@b+/g);

将产生

["aaa@bbb", "aaaa@bbbb"]