Formal comparisons of program modification

This work adopts a psychologically motivated evaluative framework in the comparison of a visual and a textual programming language. The framework used is a formal interpretation of cognitive dimensions, focusing upon the notion of notation viscosity. In contrast to many studies of visual languages, we do not primarily focus upon programs, but on program modification. Hence, a program (visual or textual) is viewed as an artifact which is manipulated by programmers. Thus in general the question addressed is one of how do visual and textual languages differ in terms of the artifact which programmers interactively manipulate. More specifically, we are able to demonstrate the use of an evaluative framework in the comparative assessment of visual and textual programming languages