A common issue that arises with text files (e.g., R code) is to identify changes that have been made between versions. I usually number my R files as file1.R, file2.R, etc. (with “file” replaced by something more meaningful),with the number indicating the version of the file. Version numbers change whenever I send the file to someone else to modify, or whenever I make major changes myself. I often need to know what changes have been made between successive …