Reactors

I need some help from experienced users. I have inserted the reactor
(below) into my acad.lsp file. It does not work as I expected. This is
my first attempt to use reactors, so obviously I am missing something.
Can someone point me in the right direction?
Note: I took the items listed from Cadalyst hoping when I save a dwg it
would zoom to extents and delete any unused objects/layers. TIA

(vl-load-com)
(setq MyReactor1
(vlr-dwg-reactor
;nil
'(vlr-BeginSave . DoThisBeforeSave)
)
)
)
(defun DoThisBeforeSave (Caller CmdSet)
(alert "You are about to save this drawing!")
(princ)
)
(defun DoThisBeforeSave (caller CmdSet)
(command ".zoom" "e")
)
(defun DoThisBeforeSave (caller CmdSet)
(command "-purge" "a" "*" "n")
(princ)
)

 

I guess the function "DoThisBeforeSave" must be placed before "setq
MyReactor1" also it shoudn't be defined 3 times. And the most important
thing - reactor must be deactivated after it's finished, otherwise it won't
work properly and moreover ACad may even crash.

 

I read about that sample from the original author and the whole article and is wrong.

To start, in the callback functions you do not use the COMMAND calls.

Second, it does not work the zoom extents on the drawing, there is something else that needs to be done.

LE.

 

Thanks - Luis helped me so it is a moot question now.