Re: How to delete all nil properties from a plist?

[John Mastro]

>     (defun plist-drop-nil-props (plist)
>       (let* ((result (list 'head))
>              (last result))
>         (cl-loop for (key val) on plist by #'cddr do
>                  (when-let (new (and val (list key val)))
>                    (setcdr last new)
>                    (setq last (cdr new))))
>         (cdr result)))

Or the same thing with `while' in place of `cl-loop':

    (defun drop-nil-props (plist)
      (let* ((result (list 'head))
             (last result))
        (while plist
          (let* ((key (pop plist))
                 (val (pop plist))
                 (new (and val (list key val))))
            (when new
              (setcdr last new)
              (setq last (cdr new)))))
        (cdr result)))

-- 
john