[Armedbear-ticket] [armedbear] #368: File level define-setf-expander is not available for expansion unless wrapped in an eval-when

[armedbear]

#368: File level define-setf-expander is not available for expansion unless
wrapped in an eval-when
-----------------------+-----------------------
  Reporter:  mevenson  |      Owner:
      Type:  defect    |     Status:  new
  Priority:  major     |  Milestone:  1.4.0
 Component:  java      |    Version:  1.4.0-dev
Resolution:            |   Keywords:
-----------------------+-----------------------

Comment (by mevenson):

 The exact conditions to trigger this problem are not simple, as the
 following works in both interpreted and compiled modes

 {{{
 ;;<file:///opt/local/share/doc/lisp/HyperSpec-7-0/HyperSpec/Body/m_defi_3.htm>

 (defun lastguy (x)
   (car (last x)))

 (define-setf-expander lastguy (x &environment env)
   "Set the last element in a list to the given value."
   (multiple-value-bind (dummies vals newval setter getter)
       (get-setf-expansion x env)
     (let ((store (gensym)))
       (values dummies
               vals
               `(,store)
               `(progn (rplaca (last ,getter) ,store) ,store)
               `(lastguy ,getter)))))

 (defun use-lastguy ()
   (let ((a `(1 2 3 4)))
     (setf (lastguy a) 42)
     a))
 }}}

--
Ticket URL: <http://abcl.org/trac/ticket/368#comment:2>
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