We developed a novel node-link style interface that can be introduced into a block-based visual programming language as an alternative representation of named variables. By using our new interface, the programmer no longer needs to decide the name of a variable. Tracking the data flow in the program can be easily achieved. Since keyboard typing is not required, the coding is expected to be more accessible to children and persons with disabilities, and it is also suitable for touch operations on mobile phones and tablets. In our system, as the number of variables increases, the intersections of the links increase, which makes the appearance complicated. To avoid this problem, we implemented improvements in the design, such as emphasizing the focused link list, and making the curves of the links consistent.