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ANTLR4 lexer rule with @init block

I have this lexer rule defined in my ANTLR v3 grammar file - it maths text in double quotes. I need to convert it to ANTLR v4. ANTLR compiler throws an error 'syntax error: mismatched input '@' expecting COLON while matching a lexer rule' (in @init line). Can lexer rule contain a @init block ? How this should be rewritten ? 

DOUBLE_QUOTED_CHARACTERS
@init 
{
   int doubleQuoteMark = input.mark(); 
   int semiColonPos = -1;
}
: ('"' WS* '"') => '"' WS* '"' { $channel = HIDDEN; }
{
    RecognitionException re = new RecognitionException("Illegal empty quotes\"\"!", input);
    reportError(re);
}
| '"' (options {greedy=false;}: ~('"'))+ 
  ('"'|';' { semiColonPos = input.index(); } ('\u0020'|'\t')* ('\n'|'\r'))
{ 
    if (semiColonPos >= 0)
    {
        input.rewind(doubleQuoteMark);

        RecognitionException re = new RecognitionException("Missing closing double quote!", input);
        reportError(re);
        input.consume();            
    }
    else
    {
        setText(getText().substring(1, getText().length()-1));
    }
}
;

Sample data:

  1. " " -> throws error "Illegal empty quotes!";
  2. "asd -> throws error "Missing closing double quote!"
  3. "text" -> returns text (valid input, content of "...")

Answer*

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1
  • LEXER RULES does not take init and after blocks.
    – Tyagi Akhilesh
    Commented Jan 4, 2019 at 14:33