print(re.findall("(as)|3","3as")) 为什么执行结果是 ['', 'as'] 怎么会出现一个空字符串呢,谢谢
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frostming Mar 20, 2018  1
https://docs.python.org/2/library/re.html#re.findall
If one or more groups are present in the pattern, return a list of groups; 如果有分组则返回分组，你这里有分组，但‘ 3 ’没有分组，所以匹配到了 3，仍返回了一个空 |
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