antlr4 - ANTLRv4: How to read double quote escaped double quotes in string?

Question

In ANTLR v4, how do we parse this kind of string with double quote escaped double quotes like in VBA?

for text:

"some string with ""john doe"" in it"

the goal would be to identify the string: some string with "john doe" in it

And is it possible to rewrite it to turn double double quotes in single double quotes? "" -> "?

Answer 1

像这样：

STRING
 : '"' (~[\r\n"] | '""')* '"'
 ;

其中~[\r\n"] | '""'意味着：

~[\r\n"]    # any char other than '\r', '\n' and double quotes
|           # OR
'""'        # two successive double quotes

是否可以重写它以将双双引号变成单双引号？

并非没有嵌入自定义代码。在 Java 中可能看起来像：

STRING
 : '"' (~[\r\n"] | '""')* '"' 
   {
     String s = getText();
     s = s.substring(1, s.length() - 1); // strip the leading and trailing quotes
     s = s.replace("\"\"", "\""); // replace all double quotes with single quotes
     setText(s);
   }
 ;