Problem
Actually this problem occurred when i was doing integration two projects. [Phase1 and phase2 of a project] . Phase 2 is developed on top of the phase1. Parallel phase1 had changed lot . Mean time those were working on phase2 has commented existing phase 1 code without comments . Phase 1 and phase 2 merged with some conflicts. So we commented such places with the descriptive comment . After merged the result code base has merged those phase 2 commented parts. Also there was some of already dead code in phase 1. So it is difficult to understand weather this is actual dead code or commented one from phase 2.
Mistake
Had left dead dead code and missing comments .
Lesson learned
Normally developers leave dead code in their original code with the mind of future purpose. But this not a good habit to continue.As long as you use source control ,earlier code may exist. Problem will occur if you are not using such version control. In such a situation you can keep dead code with descriptive comment . Otherwise omit them . That is the best way to achieve clean code.
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