anchor.diff:    @override
     TypedLiteral parseListOrMapLiteral(analyzer.Token modifier, String code) {
       String literalCode = modifier != null ? '$modifier $code' : code;
  -    return _parseExpression(literalCode);
  +    return parsePrimaryExpression(literalCode) as TypedLiteral;
     }
   
     @override
  
positive.code: 
    @override
    Expression parsePrimaryExpression(String code) {
      return _parseExpression(code);
    }
  
    @override
  
negative.code:   Expression _parseExpression(String code) {
      var statement = parseStatement('$code;') as ExpressionStatement;
      return statement.expression;
    }
  
    Object _runParser(
  