Managing Duplicated Code with Linked Editing

We present Linked Editing, a novel, lightweight editor-based technique for managing duplicated source code. Linked Editing is implemented in a prototype editor called Codelink. We argue that the use of programming abstractions like functions and macros-the traditional solution to duplicated code-has inherent cognitive costs, leading programmers to chronically copy and paste code instead. Our user study compares functional abstraction with Linked Editing and shows that Linked Editing can give the benefits of abstraction with orders of magnitude decrease in programming time.