Complexity metric based source code transformation of Erlang programs

In this paper we are going to present how to use an analyzer, which is a part of the RefactorErl [10, 12, 13], that reveals inadequate programming style or overcomplicated erlang [14, 15] program constructs during the whole lifecycle of the code using complexity measures describing the program. The algorithm [13], which we present here is also based upon the analysis of the semantic graph built from the source code, but at this stage we can define default complexity measures, and these defaults are compared to the actual measured values of the code, and so the differences can be indicated. On the other hand we show the algorithm measuring code complexity in Erlang programs, that provides automatic code transformations based on these measures. We created a script language that can calculate the structural complexity of Erlang source codes, and based on the resulting outcome providing the descriptions of transformational steps. With the help of this language we can describe automatic code transformations based on code complexity measurements. We define the syntax [11] of the language that can describe those series of steps in these automatic code refactoring that are complexity measurement [7, 9] based, and present the principle of operation of the analyzer and run-time providing algorithm. Besides the introduction of the syntax and use cases, We present the results we can achieve using this language. Keywords: software metrics, complexity, source code, refactorer