anchor.diff:  
   MULTI_COMMENT
       :   '/*'
  -        (    ~('/'|'*'|EOF)
  +        (    ~('/'|'*')
           |    ('/' ~'*') => '/'
           |    ('*' ~'/') => '*'
           |    MULTI_COMMENT
  
positive.code: 
  fragment STRING_START:;
  STRING_LITERAL
      :   '"' StringPart ( '"' | '``' { $type = STRING_START; } (('`' ~'`') => '`')?  | (EOF)=> )
      ;
  
  fragment STRING_MID:;
  STRING_END
      :   '``' StringPart ( '"' | '``' { $type = STRING_MID; } (('`' ~'`') => '`')?  | (EOF)=> )
      ;
  
  VERBATIM_STRING
      :	'"""' (~('"'|EOF) | '"' ~('"'|EOF) | '""' ~('"'|EOF))* ('"""' ('"' '"'?)? | (EOF)=> )
      ;
  
  /*
  
negative.code: */
  fragment
  StringPart
      : ( ~('\\' | '"' | '`') | ( ('`' ~'`') => '`' ) | EscapeSequence )*
      ;
  
  fragment
  EscapeSequence 
      :   '\\' 
          ( ~'{' | '{' (~'}')* '}'? )?
      ;
  
  WS  
  