How do I format dates without padding the values?

Question

I was not very statisfied with the leading zero that I got in my insert-date function.

It looks now as 09 jun 2015, instead 9 jun 2015.

To solve this, I looked into the source code of s.el and wrote a function for it.

(defun insert-date ()
  "Insert current date 1 jun yyyy."
  (interactive)
  (insert
   (if (string-prefix-p "0" (format-time-string "%d"))   ;; Checks if there is a leding zero. 
       (s-right (format-time-string "%d") 1)             ;; If so, chop it off with the library s, then s-right. 
     (format-time-string "%d"))                          ;; If not (for example, 10, 12, 25, 31), let it so. 
   (format-time-string "%b %Y"))                         ;; Then the rest (jun 2015). 
  ) 

After some tweaking, I still got the same error that there is a wrong type argument in sequencep 1. But I couldn't figure out.

Anybody have the golden hint?

Answer 1

If you look in the documentation for #'format-time-string (try C-h f format-time-string), it explains %d and %e.

%d is the day of the month, zero-padded, %e is blank-padded.

But it also goes on to say:

Certain flags and modifiers are available with some format controls.
The flags are `_', `-', `^' and `#'.  For certain characters X,
%_X is like %X, but padded with blanks; %-X is like %X,
but without padding.

So let's try it!

(let ((time (date-to-time "June 9 12:00 2015")))
  (format-time-string "%-e %b %Y" time))

results in 9 Jun 2015, with no padding at all.

The flag - is easier than trimming the string, as it also works if you want to use a numeric value inside the string, for example:

(let ((time (date-to-time "June 9 12:00 2015")))
  (format-time-string "%-e/%-m/%Y" time))

results in 9/6/2015.

Answer 2

The user nanny solved it with

(string-trim (format-time-string "%e %b %Y"))

I didn't wanted the %e becauses it added a space. But I never knew the function string-trim chops the spaces off.