How to get rid off the annoying (Lisp Expression) message when undoing a lisp routine

[MJLM]

Having already asked with no replies some time ago, I thought I could give it a try once again.

When I run my lisp routine which begins with

(command "_.undo" "_BE")

and ends with

(command "_.undo" "_E")

and for any reason I press "u" I get the annoying message (Lisp Expression) multiple times at the command prompt.

20170322-14-12-33.jpg

Is there a way to hide this repeated message or get rid off it with any other way?

Thank you.

[broncos15]

I don't know of anyway to get rid of that echo. However, I would also suggest not using the command function, but rather Visual LISP for undo. Lee Mac's code is really nice for this:

;; Start Undo  -  Lee Mac
;; Opens an Undo Group.
(defun LM:startundo ( doc )
    (LM:endundo doc)
    (vla-startundomark doc)
)
;; End Undo  -  Lee Mac
;; Closes an Undo Group.
(defun LM:endundo ( doc )
    (while (= 8 (logand 8 (getvar 'undoctl)))
        (vla-endundomark doc)
    )
)
;; Active Document  -  Lee Mac
;; Returns the VLA Active Document Object
(defun LM:acdoc nil
    (eval (list 'defun 'LM:acdoc 'nil (vla-get-activedocument (vlax-get-acad-object))))
    (LM:acdoc)
)

[MJLM]

I m not sure I used Lee's code the right way but I tried like this

(LM:startundo (LM:acdoc))

...
main code here
...

(LM:endundo (LM:acdoc))

but I didn"t notice any difference. Did I do something wrong?

Btw, why should I use this way and not native undo command? Just to suppress the messages or is there any other advantage?

[broncos15]

One of the main advantages is that you can have it in an error handler without needing to do push-error-using-command. Also, it is typically faster to not use AutoCAD commands in a LISP program.

[MJLM]

Thanks but is this the way I should use the routine like I wrote above?

[Grrr]

I was thinking about creating an vlr-Command-reactor or vlr-Undo-reactor that turns off/on the cmdecho variable, but my attempt failed.

[BIGAL]

My question is why are you using "Undo" are you doing some form of intersecting lines etc and working out points so the objects are removed if so use a (setq objx entlast) then at right point vla-delete objx. You will not see any prompts. I do this a lot where I need to work out a point.

[MJLM]

I use undo just to be able to undo the entire lisp routine. That s all. The routine has multiple steps.. The main structure is basically a 'cond' with various options, edit a selection of blocks, delete entire group, change other parameters etc. The cond command is inside a while loop so that the user can keep editing groups without the need to exit the routine every time. That I believe increases the steps written in memory to undo later. If I don't use the undo BE and E procedure then I will have to undo every step one by one which is not acceptable. By the way, The undo I showed above works fine, it s only the messages I keep getting the issue.

[BIGAL]

After 40+ years of lisp the amount of times I have used undo is almost non measurable, It sounds to me that you need to really explain why you are using undo and not remembering entities that you can do some thing with at the end.

undo the entire lisp routine

Does not make any sense.

[MJLM]

I don't need to explain anything further. I wrote above. If you really want to help other than just through meaningless info, show how this could be made and let a fellow learn something new. I though this forum was for that.

If something does not make sense for you, it may make sense for somebody else.