Union => option to keep originals

Hi,

I'm trying to get some code working.

The idea is based upon the subtract function Gilles Chanteau wrote.

Only with a twist to make this happen for union. This way you can keep the primitives at the same time.

http://gilecad.azurewebsites.net/LISP/Soustrac.lsp

MY CODE SOFAR

;; based on SOUSTRAC (gile)
;; translated, please visit [url]http://gilecad.azurewebsites.net/LISP/[/url] 
;; Performs union regions or 3D solids without making union
;; Proposes to delete or keep the removed items
(defun c:uni (/ *error* ss1 ss2 n lst)
 (vl-load-com)
 
 (or *acdoc*
     (setq *acdoc* (vla-get-activeDocument (vlax-get-acad-object)))
 )
;;;(command "vscurrent" "2Dwireframe")
;;;(setvar "NAVVCUBEDISPLAY" 3)
 
 (defun *error* (msg)
   (and
     msg
     (/= msg "function canceled")
     (princ (strcat "\nError: " msg))
   )
   (vla-EndUndoMark *acdoc*)
   (princ)
 )
 (princ
   "\nSelect solids and regions to remove .."
 )
 (if
   (setq ss1 (ssget '((0 . "REGION,3DSOLID"))))
    (if (and
   (princ
     "\nSelect solids and regions to subtract .."
   )
   (setq ss2 (ssget '((0 . "REGION,3DSOLID"))))
 )
      (progn
 (vla-StartUndoMark *acdoc*)
 (repeat (setq n (sslength ss2))
   (setq
     lst
      (cons
 (vlax-ename->vla-object (ssname ss2 (setq n (1- n))))
 lst
      )
   )
 )
        
        (foreach o lst
     (and (= (vla-get-ObjectName obj) (vla-get-ObjectName o))
   (vla-Boolean obj acUnion (vla-copy o))
     )
   )
        
 (repeat (setq n (sslength ss1))
   (setq
     obj (vlax-ename->vla-object (ssname ss1 (setq n (1- n))))
   )
   (foreach o lst
     (and (= (vla-get-ObjectName obj) (vla-get-ObjectName o)) ; I NEED A COPY OF BOTH SS1 AND SS2
   (vla-Boolean obj acUnion (vla-copy o))
     )
   )
 )
 (initget "Yes No")
 (if (= "Yes" (getkword "\nDelete United objects [Yes / No] <N>: "))
      (mapcar 'vla-delete lst)
 )
 (*error* nil)
      )
    )
 )
)