ANTLR: handle nested line comments

Question

Usually, (for syntax coloring) I use following ANTLR lines (eg for Java or C++ sources) to detect block comments ( /* this is a comment */ ):

BlockComment
    :
      '/*' BlockCommentChar* '*/'
      -> skip
    ;

fragment BlockCommentChar
    : '*'  ~'/'
    | ~'*'
    ;

But in the V language block comments are allowed to be nested. I could imagine to somehow increase a counter at a detected /* and decrease it on */ , but how to do that and how to report everything between the /* fdksjfldjlf /* fjdsjfkds f */ jfdjf jd */ as one lexer token?

Answer 1

Something like this should work:

BlockComment
 : '/*' ( BlockComment | '/' ~'*' | ~'/' )*? '*/'
 ;