A measure of program nesting complexity

For more than a decade, metrics of software complexity has been an intriguing topic for discussion. Many metrics have been proposed. Among them, the cyclomatic complexity metric is the easiest to understand and compute. In this paper, the cyclomatic complexity metric and its extensions are reviewed. The strengths and weaknesses of the cyclomatic metric are identified. One of the major weaknesses of the cyclomatic metric as well as its extensions is that they are insensitive to the level of nesting within various constructs. To remove this shortcoming, a "nesting" com­ plexity metric is proposed. The process of deriving this new metric is described in this paper. This new metric is proved to be superior to the cyclomatic metric in reflecting program complexity.