[RP] persistence of window numbers?

[Joe Corneli]

(mapcar 'string-to-number (split-string (ratpoison-windows "%n")))
;=> (2 5)

(ratpoison-number 1 5)
;=> ""

(mapcar 'string-to-number (split-string (ratpoison-windows "%n")))
;=> (1 5)


But wait a second, I thought I just changed window 5 to be window 1.

number N TARGET
     Set a window's number to N. If another window occupies the
     requested number already, then the windows' numbers are swapped.

     The second argument, TARGET, is optional. It should be the number
     of the window whose number will be changed. If TARGET is omitted
     ratpoison defaults to the current window.

Why wasn't the return value of the last function call (1 2) instead of
(1 5)?

Note that if I switch to window 5 and run (ratpoison-number 1) there,
things work as expected.

Joe