abstract = "Genetic improvement uses automated search to find
improved versions of existing software. Edit sequences
have been proposed as a very convenient way to
represent code modifications, focusing on the changes
themselves rather than duplicating the entire program.
However, edits are usually defined in terms of
practical operations rather than in terms of semantic
changes; indeed, crossover and other edit sequence
mutations usually never guarantee semantic
preservation. We propose several changes to usual edit
sequences, specifically augmenting edits with content
data and using fuzzy matching, in an attempt to improve
semantic preservation.",