private ExpressionNode DboolExpression() throws SyntaxException {
        try {
            ExpressionNode result = AExpression();

            while (iterator.current().type().is(Token.Type.BitwiseShift)) {
                BinaryOperationNode.Operation operation = null;
                Position pos = iterator.current().coordinates().starting();
                switch (iterator.current().type()) {
                    case BITWISE_SHIFT_LEFT:
                        operation = BinaryOperationNode.Operation.BITWISE_SHIFT_LEFT;
                        break;
                    case BITWISE_SHIFT_RIGHT:
                        operation = BinaryOperationNode.Operation.BITWISE_SHIFT_RIGHT;
                        break;
                    default:
                        return ExpressionNode.InvalidNode(pos);
                }
                nextToken();
                ExpressionNode right = AExpression();
                result = new BinaryOperationNode(operation, result, right, pos);
            }

            return result;
        } catch(SyntaxException ex) {
            throw ex;
        } catch(Exception ex) {
            throw (NonAnalysisException)new NonAnalysisException(ex)
                    .initPosition(iterator.current().coordinates().starting())
                    .Log("ru.bmstu.iu9.compiler.syntax");
        }
    }