anchor.diff:      :   'try'
       ;
   
  +RETRY
  +    : 'retry'
  +    ;
  +
   VOID
       :   'void'
       ;
  
positive.code: //assignable can be an assignment
  statement 
      : expressionStatement
      | controlStructure
      ;
  
  
negative.code:     :   ( 'e' | 'E' ) ( '+' | '-' )? ( '0' .. '9' )+ 
      ;
  
  CHARLITERAL
      :   '@' ( ~ NonCharacterChars | EscapeSequence )
      ;
  
  QUOTEDLITERAL
      :   '\''
          StringPart
  