Abstract
The diff3 algorithm is widely considered the gold standard for merging uncoordinated changes to list-structured data such as text files. Surprisingly, its fundamental properties have never been studied in depth.
We offer a simple, abstract presentation of the diff3 algorithm and investigate its behavior. Despite abundant anecdotal evidence that people find diff3’s behavior intuitive and predictable in practice, characterizing its good properties turns out to be rather delicate: a number of seemingly natural intuitions are incorrect in general. Our main result is a careful analysis of the intuition that edits to “well-separated” regions of the same document are guaranteed never to conflict.
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Khanna, S., Kunal, K., Pierce, B.C. (2007). A Formal Investigation of Diff3. In: Arvind, V., Prasad, S. (eds) FSTTCS 2007: Foundations of Software Technology and Theoretical Computer Science. FSTTCS 2007. Lecture Notes in Computer Science, vol 4855. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-77050-3_40
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DOI: https://doi.org/10.1007/978-3-540-77050-3_40
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-77049-7
Online ISBN: 978-3-540-77050-3
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