Hi Iago,
This is not a bug. It is expected. Patterns may not overlap. However, there is a way to get the result you want using perl: ```R gsub("([aeiouAEIOU])(?=[aeiouAEIOU])", "\\1_", "aerioue", perl = TRUE) ``` The specific change I made is called a positive lookahead, you can read more about it here: https://www.regular-expressions.info/lookaround.html It's a way to check for a piece of text without consuming it in the match. Also, since you don't care about character case, it might be more legible to add ignore.case = TRUE and remove the upper case characters: ```R gsub("([aeiou])(?=[aeiou])", "\\1_", "aerioue", perl = TRUE, ignore.case = TRUE) ## or gsub("(?i)([aeiou])(?=[aeiou])", "\\1_", "aerioue", perl = TRUE) ``` I hope this helps! On Fri, Mar 1, 2024, 06:37 Iago Giné Vázquez <iago.g...@sjd.es> wrote: > Hi all, > > I tested next command: > > gsub("([aeiouAEIOU])([aeiouAEIOU])", "\\1_\\2", "aerioue") > > with the following output: > > [1] "a_eri_ou_e" > > So, there are two consecutive vowels where an underscore is not added. > > May it be a bug? Is it expected (bug or not)? Is there any chance to get > what I want (an underscore between each pair of consecutive vowels)? > > > Thank you! > > Best regards, > > Iago > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.