How can I filter directory contents to return the highest numeric named directory? For example, suppose (directory-files "/some/dir") returns:
("." ".." "4.03.0" "4.02.9" "archives" "config" "log")
How can I extract the string "4.03.0"?
I tried using seq-remove with a regexp based predicate, but could not get it to work. Suggestions and insights appreciated. Thanks.
directory-files accepts match-regexp argument:
(directory-files "my/path/to/dir" nil "^[0-9][0-9.]*$")
should return ("4.03.0" "4.02.9") and you extract the first element of the list using functions first or car.
If you really want to use seq-remove, you can do that too:
(seq-remove
(lambda (s)
(not (string-match "^[0-9][0-9.]*$" s)))
'("." ".." "4.03.0" "4.02.9" "archives" "config" "log"))
==> ("4.03.0" "4.02.9")
Note that ^[0-9.]$ matches "." and "..".
directory-files ensure descending ordering? If not, is there a way to extract the target string independent of directory list order (i.e. assuming no particular order)?
– Ari
May 19 '17 at 17:18
directory-files. If that is not your question, you should close this one and ask another one.
– sds
May 19 '17 at 17:20
C-h f directory-files e.g. will tell you what the function does and what arguments it takes. There is a similar facility for variables. Just do C-h ? to get more information.
– NickD
May 19 '17 at 18:21
