Source code cloning, also known as copy and paste programming is believed to be a major threat to software systems, mostly the ones currently in their implementation phase. The problem is often overlooked due to the true danger lies in the clones' long-term existence, specifically in their unmonitored evolution – hence the immediate negative impact cannot be observed. When a clone instance of a given method needs maintenance (bug fixing) or further code development (enhancement), usually the tasks would require to be performed on the other clone instances as well for the consistency to remain.
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