"Yoel Jacobsen" <y...@emet.co.il> schrieb im Newsbeitrag
news:ctl89r$mr5$1@news2.netvision.net.il...

you can define the following macro to see what is going on:

(defmacro test1 (x) `(identity ,x))

Now my lisp answers:

CL-USER 43 > (macroexpand '(test1 '(1 2)))
(IDENTITY (QUOTE (1 2)))
T

You might also write:

(defmacro test2 (x)
  `(format t "~s" ,(format nil "~s" x)))

to see what x contains within a comma expression:

CL-USER 46 : 1 > (test2 '(1 2))
"(QUOTE (1 2))"
NIL

Thus you have (at least) two possible solutions:

(defmacro list-to-plist (plist pos-list id-list field-list)
  `(progn ,@(map 'list
                 #'(lambda (id pos)
                     `(setf (getf ,id-list ,id) (elt ,field-list ,pos)))
                 `(,@(cadr plist))
                 `(,@(cadr pos-list))
                 )))

Notice: argument to getf changed. Your function pline-to-plist remains
unchanged.

Second possiblity:

(defmacro list-to-plist (plist pos-list id-list field-list)
  `(progn ,@(map 'list
                 #'(lambda (id pos)
                     `(setf (getf ,id-list ,id) (elt ,field-list ,pos)))
                 plist
                 pos-list)))

(defun pline-to-plist (line)
   "convert a passwd line to a plist"
   (let ((fields (split-sequence:split-sequence #\: line))
                 (entry nil))
     (list-to-plist
       (:login :passwd :uid :gid :group :home :shell)
       (0 1 2 3 4 5 6 7)
       entry fields)
     entry))

Notice: the quotes in pline-to-plist are gone.

I'd utterly agree to Kenny. Lisp is different! At least for me. For most
other languages I roughly browsed a nice book.  To explore its strength Lisp
needs studying literature. Here are some suggestions:

http://www.alu.org is a good starting point.
http://www.gigamonkeys.com/book is great compact and easy to read (my
opinion)
http://www.paulgraham.com/onlisp.html is a standard

Hope this helps a bit further.