Initget causes lisp routine to halt

Donald Broussard
Donald Broussard
in Programming and customization
I'm trying to implement an undo option in a lisp routine. The lisp routine stops executing at the (initget "Undo") line. Why?

(while
(initget "Undo")
(setq sEntity (nentsel "\nSelect object or [Undo] >"))

(if (= sEntity "U")
(progn
(command "_.vplayer" "_t" sLayer "_c" "")
(command "HASD:ViewportLayerFreeze")
)
(setq sEntName (car sEntity))
)
(setq sCLayer (getvar "CLAYER"))
(setq sLayer (cdr (assoc 8 (entget sEntName))))
(if (= sLayer sCLayer)
(progn
(command "_.layer" "_s" "0" "_off" sLayer "")
(setq sMsg
(strcat
"\nThe selected layer, " sLayer ", is the current layer."
"\nIt has been turned off instead of frozen in the viewport."
)
)
(dcl-MessageBox sMsg "HASD-Info" 2 2)
)
(command "_.vplayer" "_f" sLayer "_c" "") ;this line is the real functionality
)
(princ)
)

Comments

  • Jason Bourhill
    Jason Bourhill
    Your using (initget "Undo") as the test expression for the while statement. Initget returns nil, so while would immediately exit. I assume that you've missed your intended test expression.

    I also don't see any statements that end the while loop, which means it would loop endlessly.

    Regards,
    Jason Bourhill

  • Donald Broussard
    Donald Broussard
    I want to loop as long as the user is selecting objects and provide the opportunity to undo the last action or layer freeze in this case. I don't really have a test expression?
  • Donald Broussard
    Donald Broussard
    I included a dummy condition and the tool is working ... thanks.

    I wish I knew more :o/
  • Roy Klein Gebbinck
    Roy Klein Gebbinck
    This is a case where using progn is more appropriate I think:
    [code](while
      (progn
        (initget "Undo")
        (setq sEntity (nentsel "\nSelect object or [Undo] >"))
      )
      ...
    )[/code]
This discussion has been closed.