Program indentation and comprehensibility

Abstract

The consensus in the programming community is that indentation aids program comprehension, although many studies do not back this up. We tested program comprehension on a Pascal program. Two styles of indentation were used--blocked and nonblocked--in addition to four passible levels of indentation (0, 2, 4, 6 spaces). Both experienced and novice subjects were used. Although the blocking style made no difference, the level of identation had a significant effect on program comprehension. (2--4 spaces had the highest mean score for program comprehension.) We recommend that a moderate level of indentation be used to increase program comprehension and user satisfaction. © 1983, ACM. All rights reserved.