A Look at Programmers Communicating through Program Indentation

Fundamental to the maintenance of computer programs is software comprehension – the ability to understand what a program does and how it does it. Software comprehension involves reconstructing the logic, structure, and goals of the programmer who originally wrote the program. A number of techniques have been developed to increase the comprehensibility of software by facilitating the implicit communication between the original programmer and succeeding programmers. One such technique is physically structuring the code to communicate program structure. The most common form of physical structuring is indentation. Although intuition suggests that using a physical structure to highlight a conceptual structure should be helpful, research has not always supported the value of using indentation in communicating program structure. This research examined earlier work on indentation and identified methodological flaws that may have contributed to the lack of effect of indentation on program comprehensibility. The data from this research suggest that indentation does communicate certain types of information about program structure. Implications of these results for programmers trying to appropriately structure their code for future use are described.