Design of a visual environment for programming by direct data manipulation

Abstract: The use of applications on computers, smartphones, and tablets has been considerably simplified thanks to interactive and dynamic graphical interfaces coupled with the mouse and touch screens. It is no longer necessary to be a computer specialist to use them. Paradoxically, the development of computer programs generally requires writing lines of code in a programming language whose syntax is particularly strict. This process poses many difficulties for programmers. We propose an original tool in which arbitrary programs (Turing-complete) can be developed in a completely visual manner by direct manipulation of the data, without writing a line of code. The user can thus develop an algorithm by directly visualizing the result of actions taken on the data. A method for constructing iterations is associated with the tool. It proposes to create each part, including the loop body, in a non-linear manner under visual control of the state of the data. In addition, the tool supports the production of lines of code in several languages including Python, C, Java, that correspond to the actions performed. In this article, we present the tool, the design choices, the problems to be solved, and the limits and the contributions of the direct-data-manipulation approach.