用于匹配未被引号括起的逗号的正则表达式

I'm using Clojure, so this is in the context of Java regexes.

我正在使用Clojure，所以这是在Java正则表达式的上下文中。

Here is an example string:

这是一个示例字符串：

{:a "ab,cd, efg", :b "ab,def, egf,", :c "Conjecture"}

The important bits are the commas after each string. I'd like to be able to replace them with newline characters with Java's replaceAll method. A regex that will match any comma that is not surrounded by quotes will do.

重要的位是每个字符串后面的逗号。我希望能够用Java的replaceAll方法用换行符替换它们。正则表达式将匹配任何未被引号括起的逗号。

If I'm not coming across well, please ask and I'll be happily to clarify anything.

如果我没遇好，请问，我会高兴地澄清一切。

edit: sorry for the confusion in the title. I haven't been awake very long.

编辑：对不起标题中的混淆。我没有醒来很久。

String: {:a "ab, cd efg",} <-- In this example, the comma at the end would be matched, but the ones inside the quote would not.

字符串：{：a“ab，cd efg”，} < - 在此示例中，末尾的逗号将匹配，但引号内的逗号不匹配。

String: {:a 3, :b 3,} <-- Every single comma matches.

字符串：{：a 3，：b 3，} < - 每个逗号匹配。

String {:a "abcd,efg" :b "abcedg,e"} <-- Every single comma doesn't match.

String {：a“abcd，efg”：b“abcedg，e”} < - 每个逗号都不匹配。

1 个解决方案

#1

The regex:

正则表达式：

,\s*(?=([^"]*"[^"]*")*[^"]*$)

Matches:

火柴：

{:a "ab,cd, efg", :b "ab,def, egf,", :c "Conjecture"}
                ^                  ^
                ^                  ^

and:

和：

{:a "ab, cd efg",}
                ^
                ^

and does not match a comma in:

与逗号不匹配：

{:a "abcd,efg" :b "abcedg,e"}

But when escaped quotes can appear, like so:

但是当出现转义引号时，就像这样：

{:a "ab,\" cd efg",} // only the last comma should match

then a regex solution won't work.

然后正则表达式解决方案将无法正常工作。

A brief explanation of the regex:

正则表达式的简要说明：

,            # match the character ','
\s*          # match a whitespace character: [ \t\n\x0B\f\r] and repeat it zero or more times
(?=          # start positive look ahead
  (          #   start capture group 1
    [^"]*    #     match any character other than '"' and repeat it zero or more times
    "        #     match the character '"'
    [^"]*    #     match any character other than '"' and repeat it zero or more times
    "        #     match the character '"'
  )*         #   end capture group 1 and repeat it zero or more times
  [^"]*      #   match any character other than '"' and repeat it zero or more times
  $          #   match the end of the input
)            # end positive look ahead

In other words: match any comma that has zero, or an even number of quotes ahead of it (until the end of the string).

换句话说：匹配任何前面有零或者偶数引号的逗号（直到字符串结尾）。

#1