Python 中的正则表达式 [^.]
import re
str="Everyone loves Stack Overflow"
print(re.findall("[ESO][^.]",str))
我不明白为什么 [^.] 会做任何事情。我认为它只匹配不是字符的字符 - 换句话说：什么都没有！但输出如下：
['Ev', 'St', 'Ov']
有人可以解释一下吗？在谷歌上搜索像 [^.] 这样的东西是不可能的，关于正则表达式的 pythondocs 也没有帮助。
import re
str="Everyone loves Stack Overflow"
print(re.findall("[ESO][^.]",str))
I don't understand why [^.] does anything. I thought it only matches characters that are not characters - in other words: nothing! But the output is the following:
['Ev', 'St', 'Ov']
Can someone shed some light on this? It's impossible to search for something like [^.] on google, and pythondocs about regular expressions didn't help either.
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大多数正则表达式特殊字符会失去其在字符类（方括号）中的特殊含义，因此，虽然
.匹配任何字符，但[.]匹配文字.和[^.]匹配.以外的任何字符。有时您会看到人们将像.这样的字符放在方括号中，只是为了确保按字面意思处理它，而不必担心正则表达式库中的任何极端情况。Most of the regular expression special characters lose their special meaning within a character class (square brackets), so while
.matches any character,[.]matches a literal.and[^.]matches any character other than.. You will sometimes see people wrap a character like.in square brackets just to make sure it's treated literally without having to worry about any corner cases in a regular expression library.字符类
[]有自己的小语言。具体来说，字符类中的点.与实际的.匹配（并且不是通配符）。Character classes
[]have their own little language. Specifically, the dot.inside a character class matches the actual.(and is not a wildcard).大多数字符在字符组内时会失去其特殊含义。
因此
.匹配任何字符，但[.]仅匹配点。因此[^.]匹配除点之外的所有内容。Most characters lose their special meaning when they are inside a character group.
So
.matches any character, but[.]matches only dot. Thus[^.]matches everything that is not dot.