global variables question

For the past year or so I've been running with some globals set for the
convenience of several vla routines
they are loaded from a lisp file Globals.lsp which is called by acaddoc.lsp
and therefore loads with each dwg.
ex:
(vl-load-com)
(or *acad* (setq *acad* (vlax-get-acad-object)))
(or *doc* (setq *doc* (vla-get-activedocument *acad*)))
(or *Mspace* (setq *Mspace* (vla-get-modelspace *doc*)))
etc.....

I've read on this ng about the need to destroy these objects before closing
acad thus:
; Notes:
; Use a DocManagerReactor with a 'vlr-documentToBeDestroyed'-event
; to release the global objects at the end of a session - otherwise
AutoCAD may crash

well, being pathologically lazy and sloppy I haven't implemented this
reactor business - guess I'm more scared of reactors than wandering
globals....

and of course acad does crash on occasion - it has always crashed on
occasion ever since I started using around rel12 dos. - so I'm so used to
that, that I can't tell any difference since I've been declaring these
globals.

so the question is, do I need to get to trying to figure out that reactor
doomahickey or is it not an urgent necessity????

and as I'm trying to think about these global objects, since this loads with
each drawing, they are just global to the document space, not to the acad
session
....is that right?

so if I have 5 drawings open I have 5 versions of *acad* and *doc*,
.... is that right?

so the reactor would be defined like also in the acaddoc.lsp file or called
from there so that it would be loaded in each drawing as well,
.... is that right?

but a docManagerReactor I would think was an Editor reactor as opposed to a
document level reactor, so maybe the above is not right?

any input on this?
tia
Mark

 

Mark,
I agree with what the others said. The most important things to remove
when the drawing is closed are REACTORS. If reactors are not
properly removed, they can continue to act without their own namespace
generating errors and, in some cases, crashing AutoCAD.

Any variables that are bound to objects internal to the documents
should be localized where possible.

I have tried to minimize my use of globals. I haven't found a significant
difference in speed except within loops in accessing the acad and document
objects with the built in functions.

Using reactors to destroy globals will certainly cause more problems than
it solves.

Regards,
Doug

 

Thanks Tony,
Once again my laziness and procrastination (at implementing the reactor)
ends up looking like disciplined self control (by eliminating unnecessary
coding). That makes me laugh!
))

I've seen it in a number of posts on this ng a while back...when the vla
discussions began to proliferate.

I paraphrased that note out of a header from a file by Menzi

; -- Function VxGetDimStyles
; Returns a list of all dimension style names
; Copyright:
; ©2001 MENZI ENGINEERING GmbH, Switzerland
; Arguments [Typ]:
; None
; Return [Typ]:
; > List of Dim style names

• 
  ; Notes:
  ; Use a DocManagerReactor with a 'vlr-documentToBeDestroyed'-event
  ; to release the Gb:AcO and Gb:AcD objects at the end of a
  ; AutoCAD session - otherwise AutoCAD maybe crashes...
  (defun VxGetDimStyles ( / DstLst)
  (setq Gb:AcO (cond (Gb:AcO) ((vlax-get-acad-object)))
  Gb:AcD (cond (Gb:AcD) ((vla-get-ActiveDocument Gb:AcO)))
  )
  (vlax-for Dst (vla-get-DimStyles Gb:AcD)
  (setq DstLst (cons (vla-get-Name Dst) DstLst))
  )
  (reverse DstLst)
  )

 

LISP is a garbage-collected (a.k.a. "Managed") language, and
there's no need to do any clean up WRT varaibles. There is
a need to disconnect reactors because the namespace where they
live can be destroyed and they'll continue to be fired.

Visual LISP does not manage reactors properly (they should
be automatically disconnected when the namespace containing
them is destroyed).

--
http://www.acadxtabs.com

 

Does this apply to simple reactors that monitor system variables such as
TILEMODE to change LTSCALE/DIMSCALE ?
We have a lot of sporadic crashing in the office and I'd like to clean up
what ever I can.

If so, any tips on disconnecting reactors?

Thanks,

Dan

 

I don't use Visual LISP for much these days
(limited to very simple functions and command
scripting and testing code written in other
languages).

Most of my work is done in C++ and Delphi.

 

Luis,

Whatever help/advice you can provide would be much appreciated. I tried
emailing you at but it was rejected? Also
www.caddximation.com seems to be down?

Dan

 

rejected again from our office server, but I did send another via my
earthlink account.

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