(defun MX (/ ce ss ls no PNT1 PNT2) ;; from JAG.LSP
  (setvar "CMDECHO" 0)
  (prompt "Select cutting edges...")(terpri)
  (setq ce (ssget))(terpri)
  (prompt "Select objects to extend:")
  (terpri)
  (setq pnt1 (getpoint "First point"))
  (terpri)
  (setq pnt2 (getcorner pnt1 "2nd pnt"))
  (terpri)
  (setq ss (ssget "c" pnt1 pnt2)
    ls (sslength ss)
    no -1
  )
  (command "extend" ce "")
  (repeat ls
    (setq no (1+ no))
    (command (list (ssname ss no) pnt2))
  )
  (command "")
  
  (prin1)
)