<!doctype html public "-//W3C//DTD W3 HTML//EN">
<html><head><style type="text/css"><!--
blockquote, dl, ul, ol, li { padding-top: 0 ; padding-bottom: 0 }
--></style><title>Does *anyone* use MVC? (was: Re: [BUG?] weird
behaviou</title></head><body>
<div>It seems to me that no Squeaker could plausibly have been doing
any real work in MVC in any 3.2 or 3.3a since this bug arrived more
than eight months ago, because the mere raising of a single debugger
would have put his environment into a state no reasonable person could
tolerate. And he would therefore have screamed and we would have
heard.</div>
<div><br></div>
<div>Consequently, I'm not too surprised that there has not been a
single response posted to this thread, other than Boris's original bug
report and my reply.</div>
<div><br></div>
<div>But is it really true that there are actually *no* MVC
practitioners using either Squeak 3.2 or 3.3a , no one at all, except
Boris?</div>
<div><br></div>
<div>Cheers,</div>
<div><br></div>
<div> -- Scott</div>
<div><br></div>
<div><br></div>
<div>At 2:46 AM -0700 7/30/02, Scott Wallace wrote:</div>
<blockquote type="cite" cite>The mvc brain-damage Boris describes
turns out to be reliably exhibited whenever a debugger is presented
and proceeded-through in an MVC project, both in 3.2 *and* 3.3a.
Even something as simple as hitting cmd-dot and then hitting the
Proceed button on the ensuing pre-debug window (in mvc) will do
it.</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>By going back to an image that did not
exhibit these problems and then loading updates one at a time,
checking for the bug after each update, I was able to track down
exactly where this problem entered into Squeak.</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>It turns out to have arrived in update
4487SyntaxErrorsOnFileIn-svp, whose preamble was:</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite"
cite>--------------------------------------------------</blockquote>
<blockquote type="cite" cite><i>Change Set:<x-tab>
</x-tab><x-tab>
</x-tab>SyntaxErrorsOnFileIn-svp</i></blockquote>
<blockquote type="cite" cite><i>Date:<x-tab>
</x-tab><x-tab>
</x-tab><x-tab> </x-tab>14
October 2001<br>
Author:<x-tab>
</x-tab><x-tab>
</x-tab><x-tab>
</x-tab>Stephen Pair<br>
<br>
BugFixing Party @ Camp Smalltalk OOPSLA 2001. Fixes bug report
from Sept 13, 2001:</i><br>
</blockquote>
<blockquote type="cite" cite><i>If you get a syntax error during a
fileIn, you should be able to correct it in the notifier, and then
accept the corrected code from that window. If all is well, the method
gets defined, and the fileIn continues. But it doesn't. Instead, you
get... NonBooleanReceiver: proceed for truth.</i></blockquote>
<blockquote type="cite"
cite>--------------------------------------------------</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>That update may have improved things
regarding the state after syntax errors are encountered during
fileins, but it is seemingly directly responsible for breaking mvc
whenever a debugger is put up.</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>It appears that a simple reversion of the
single method in this update (Debugger >>
process:controller:context:isolationHead:) cures the problem, though
presumably that would re-establish the problem on file-in that the
update was intended to fix.</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>I attach herewith instead a proposed
workaround, with the following preamble:</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite"
cite>--------------------------------------------------</blockquote>
<blockquote type="cite" cite>Change Set:<x-tab>
</x-tab><x-tab>
</x-tab>debuggerFix-sw<br>
Date:<x-tab>
</x-tab><x-tab>
</x-tab><x-tab> </x-tab>29
July 2002</blockquote>
<blockquote type="cite" cite>Author:<x-tab>
</x-tab><x-tab>
</x-tab><x-tab>
</x-tab>Scott Wallace</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>Works around a bug introduced in
update4487SyntaxErrorsOnFileIn-svp (October 2001) which had
compromised the mvc environment whenever a debugger was brought up.
The workaround here, done without any pretension to deep knowledge of
the underlying issues, is to restore the method in question (Debugger
>> process:controller:context:isolationHead:) to its former
behavior in the mvc case, while letting it work its putative magic
when in morphic.</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite"
cite>--------------------------------------------------</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>Before I publish this -- or, preferably,
publish someone else's better fix -- as an update, I hope to hear some
confirmation or other commentary on this matter, and, ideally, to
receive the "real fix" from someone.</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>Cheers,</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite> -- Scott</blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>At 9:20 AM +0200 7/28/02, Boris Gaertner
wrote:
<blockquote type="cite" cite><font face="Arial">On windows 98 the new
Squeak 3.2 exhibits a quite strange</font></blockquote>
<blockquote type="cite" cite><font face="Arial">behaviour when a
debugger is opened in the MVC environment.</font></blockquote>
<blockquote type="cite" cite> </blockquote>
<blockquote type="cite" cite><font face="Arial">Please try
this.</font></blockquote>
<blockquote type="cite" cite><font face="Arial">1. create and enter an
mvc project.</font></blockquote>
<blockquote type="cite" cite><font face="Arial">2. open a
class</font> <font face="Arial">hierarchy
browser.</font></blockquote>
<blockquote type="cite" cite><font face="Arial">3. select
StringHolder>>browseVersions.</font></blockquote>
<blockquote type="cite" cite><font face="Arial"> ( a lot
of other methods would do as well. )</font></blockquote>
<blockquote type="cite" cite><font face="Arial">4. Insert the
statement self halt. at the beginning
of</font></blockquote>
<blockquote type="cite" cite><font face="Arial"> the
method and save the method with "accept"</font></blockquote>
<blockquote type="cite" cite><font face="Arial">5. Now, move the mouse
into the method names view</font></blockquote>
<blockquote type="cite" cite><font face="Arial"> and
select "versions"</font></blockquote>
<blockquote type="cite" cite><font face="Arial">6. a small red window
with title "Halt" and three buttons</font></blockquote>
<blockquote type="cite" cite><font face="Arial">is opened. Press the
button "Resume"</font></blockquote>
<blockquote type="cite" cite><font face="Arial">7. a blue (or violet?)
VersionsBrowser is opened. It</font></blockquote>
<blockquote type="cite" cite><font face="Arial">flashes when it is
opened and this detail is maybe</font></blockquote>
<blockquote type="cite" cite><font
face="Arial">important.</font></blockquote>
<blockquote type="cite" cite><font face="Arial">8. select a version. I
see the method text displayed</font></blockquote>
<blockquote type="cite" cite><font face="Arial">for a very short time,
then the text view is empty again.</font></blockquote>
<blockquote type="cite" cite> </blockquote>
<blockquote type="cite" cite><font face="Arial">There are also other
weird effects (on my computer at least)</font></blockquote>
<blockquote type="cite" cite> </blockquote>
<blockquote type="cite" cite><font face="Arial">*the system menue
shows unusual behavior.</font></blockquote>
<blockquote type="cite" cite><font face="Arial">*When the mouse
pointer leases the versions brwoser and</font></blockquote>
<blockquote type="cite" cite><font face="Arial">then enters it again,
it crosses the window border.</font></blockquote>
<blockquote type="cite" cite><font face="Arial">When it does, the
curser changes to a "drag window border"</font></blockquote>
<blockquote type="cite" cite><font face="Arial">symbol. That symbol
does not vanish again when the mouse</font></blockquote>
<blockquote type="cite" cite><font face="Arial">pointer is inside the
versions browser.</font></blockquote>
<blockquote type="cite" cite> </blockquote>
<blockquote type="cite" cite><font face="Arial">After a lot of
nonsensical actions with the mouse</font></blockquote>
<blockquote type="cite" cite><font face="Arial">Squeak seemingly comes
back to normal bahaviour.</font></blockquote>
<blockquote type="cite" cite> </blockquote>
<blockquote type="cite" cite><font face="Arial">I saw these strange
things also in a 3.2 alpha (last update: 4599)</font></blockquote>
<blockquote type="cite" cite><font face="Arial">with the virtual
machine</font></blockquote>
<blockquote type="cite" cite><font face="Arial">Squeak 3.2.2 VM
(release candidate) from May 26 2002</font></blockquote>
<blockquote type="cite" cite><font face="Arial">Compiler: gcc 2.95.2
19991024 (release)</font></blockquote>
<blockquote type="cite" cite> </blockquote>
<blockquote type="cite" cite><font face="Arial">I think that something
with the process switching or</font></blockquote>
<blockquote type="cite" cite><font face="Arial">scheduling goes wrong,
but until now I have no idea what</font></blockquote>
<blockquote type="cite" cite><font face="Arial">it
is.</font></blockquote>
<blockquote type="cite" cite> </blockquote>
<blockquote type="cite" cite><font face="Arial">Are there others out
there that can confirm my observations?</font></blockquote>
<blockquote type="cite" cite><font face="Arial">Have you any idea what
I can do to better the situation?</font></blockquote>
<blockquote type="cite" cite> </blockquote>
<blockquote type="cite" cite><font
face="Arial">Greetings</font></blockquote>
<blockquote type="cite" cite><font
face="Arial">Boris</font></blockquote>
</blockquote>
</body>
</html>