<div dir="ltr"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Adding an instance variable to Morph is tricky. Hence this preamble..."</blockquote><div><br></div>Thanks. Very clear. ... preamble, as in, to be performed via command line -s <script> parameter?</div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Mar 24, 2023 at 7:49 PM Juan Vuletich <<a href="mailto:juan@cuis.st">juan@cuis.st</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><u></u>
<div bgcolor="#ffffff">
Those safeguards are there for a reason. Just removing them without
really understanding what's going on is asking for trouble.<br>
<br>
To see how to do what you want to do, but in a safe way, see (for
instance) change set #4110. You'll need to unzip the relevant file
in /PreviousUpdates.<br>
<br>
Hope this helps.<br>
<br>
Cheers,<br>
<br>
On 3/24/2023 6:30 PM, Alexandre Rousseau via Cuis-dev wrote:
<blockquote type="cite">
<div dir="ltr">I just learned a new word. Thanks. :)
<div><br>
</div>
<div>
<div>I compared this behaviour to that of Squeak 6. The latter
issues a warning but in situ recompilation succeeds without
subsequent side effects, in and this and subsequent
sessions.</div>
</div>
<div><br>
</div>
<div>Even replacing "Object >> become:" with the Squeak
equivalent fails (errors). </div>
<div><br>
</div>
<div>Bummer that. Will dig deeper if I can find time and shovel.</div>
<div><br>
</div>
<div><br>
</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Fri, Mar 24, 2023 at
4:55 PM Gerald Klix <<a href="mailto:cuis.01@klix.ch" target="_blank">cuis.01@klix.ch</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
<div>Oh well, this is becoming a bigger gymkhana.<br>
<br>
I presume you have too hack <tt>Object>>#become:</tt>;
in essence disable all the checking code<br>
before <tt>{ self } elementsExchangeIdentityWith: {
otherObject }</tt>.<br>
<br>
NB:<br>
The same method in Squeak just reads:<br>
<br>
<tt>become: otherObject </tt><tt><br>
</tt><tt> "Primitive. Swap the object pointers of the
receiver and the argument.</tt><tt><br>
</tt><tt> All variables in the entire system that used
to point to the receiver now</tt><tt><br>
</tt><tt> point to the argument, and vice-versa. Fails
if either object is read-only</tt><tt><br>
</tt><tt> or is an immediate such as a SmallInteger."</tt><tt><br>
</tt><tt><br>
</tt><tt> {self} elementsExchangeIdentityWith:
{otherObject}</tt><tt><br>
</tt><tt><br>
<br>
</tt>Use the browsers "versions" button to restore the old
version.<br>
You can do all of this while the image is running.<br>
<br>
Again I learned two things:<br>
<br>
1. Juan's precautionary code in <tt>become:</tt> checks
all running processes.<br>
2. Command line parsing is done after the UI's display
process was started.<br>
<br>
See <tt>SystemDictionary>>#snapshot:andQuit:embedded:clearAllClassState:</tt>.<br>
<tt>self processCommandLineArguments </tt>comes after<tt>
<br>
UISupervisor spawnNewMorphicProcessFor: (guiRootObject
ifNil: [ guiRootObject := guiRootObjectClass newWorld
]).<br>
</tt><br>
<br>
HTH,<br>
<br>
Gerald<br>
<br>
<br>
<br>
<br>
On 3/24/23 8:09 PM, Alexandre Rousseau wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<div>Nope. This still fails ...</div>
<blockquote class="gmail_quote">./Squeak.app/Contents/MacOS/Squeak
Cuis-Smalltalk-Dev/Cuis6.0-5686.image -d "BoxedMorph
addInstVarName: 'someBorderStyle'"</blockquote>
<blockquote class="gmail_quote"> ...</blockquote>
<blockquote class="gmail_quote">Class reshaping:
WorldMorph has some instance running
#runDeferredUIMessages. This CompiledMethod would
become invalid. Class reshaping aborted.<br>
Class reshaping: WorldMorph has some instance running
#runDeferredUIMessages. This CompiledMethod would
become invalid. Class reshaping aborted.<br>
Class reshaping: WorldMorph has some instance running
#doOneCycleNow. This CompiledMethod would become
invalid. Class reshaping aborted.<br>
Class reshaping: WorldMorph has some instance running
#doOneCycle:. This CompiledMethod would become
invalid. Class reshaping aborted.<br>
Class reshaping: WorldMorph has some instance running
#mainLoop. This CompiledMethod would become invalid.
Class reshaping aborted.<br>
Class reshaping: WorldMorph has some instance running
#mainLoop. This CompiledMethod would become invalid.
Class reshaping aborted.</blockquote>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Fri, Mar 24, 2023
at 4:23 AM Gerald Klix via Cuis-dev <<a href="mailto:cuis-dev@lists.cuis.st" target="_blank">cuis-dev@lists.cuis.st</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote">
<div>
<div>On 3/24/23 8:31 AM, Alexandre Rousseau via
Cuis-dev wrote:<br>
</div>
<blockquote type="cite">
<pre>I'm trying to modify rather than subclass BoxedMorp, adding a new instance
var to the class definition. This fails while Transcript reports what
follows.
I'm guessing that recompilation of BoxedMorph does not play well while a
WorldMorph (a subclass of BoxedMorph itself) instance is running.
What would be a way to work around this?
Class reshaping: InnerTextMorph has some instance running #acceptContents.
</pre>
<blockquote type="cite">
<pre>This CompiledMethod would become invalid. Class reshaping aborted.
Class reshaping: InnerTextMorph has some instance running
#processKeystrokeEvent:. This CompiledMethod would become invalid. Class
reshaping aborted.
Class reshaping: InnerTextMorph has some instance running
#processKeystrokeEvent:. This CompiledMethod would become invalid. Class
reshaping aborted.
Class reshaping: InnerTextMorph has some instance running #keyStroke:.
This CompiledMethod would become invalid. Class reshaping aborted.
Class reshaping: InnerTextMorph has some instance running #keyStroke:.
This CompiledMethod would become invalid. Class reshaping aborted.
Class reshaping: HandMorph has some instance running
#startKeyboardDispatch:. This CompiledMethod would become invalid. Class
reshaping aborted.
Class reshaping: HandMorph has some instance running #processEventQueue.
This CompiledMethod would become invalid. Class reshaping aborted.
Class reshaping: WorldMorph has some instance running #doOneCycleNow. This
CompiledMethod would become invalid. Class reshaping aborted.
Class reshaping: WorldMorph has some instance running #handsDo:. This
CompiledMethod would become invalid. Class reshaping aborted.
Class reshaping: WorldMorph has some instance running #doOneCycleNow. This
CompiledMethod would become invalid. Class reshaping aborted.
Class reshaping: WorldMorph has some instance running #doOneCycle:. This
CompiledMethod would become invalid. Class reshaping aborted.
Class reshaping: WorldMorph has some instance running #mainLoop. This
CompiledMethod would become invalid. Class reshaping aborted.
Class reshaping: WorldMorph has some instance running #mainLoop. This
CompiledMethod would become invalid. Class reshaping aborted.
</pre>
</blockquote>
<br>
<fieldset></fieldset>
</blockquote>
First, let me analyze that problem.<br>
Nearly every Morph you see on the screen – <tt>SystemWindow</tt>
and <br>
thus <tt>BrowserWindow</tt> – is derived from <tt>BoxedMorph</tt>.
Juan added save guards<br>
to Object>>#become:, because adding the target
object of <tt>#become:</tt><br>
might still have some active contexts on the stack
and these<br>
active contexts refer to methods that where compiled
for the<br>
source object of <tt>#bceome:</tt>. In your case
the source object<br>
is the old class and the target object is the new
class, with<br>
the added instance variable. If you will add the
instance variable<br>
add the end, it would work out. Otherwise some<br>
morphic code in the running system will certainly
crash.<br>
<br>
Now for ways around this mess:<br>
<br>
Do you really need an instance variable?<br>
Morphs also have properties, that should<br>
be used if the instance variable is <tt>nil</tt>
for<br>
most morphs. Properties come in handy here,<br>
because the can be added at run-time.<br>
<br>
If you insist on adding instance variables,<br>
you have to add your variable with<br>
no morphic code on the stack, meaning you have to <br>
do it from the command line.<br>
There is a method <tt>Class>>#addInstVarName:</tt>
that lets<br>
you add instance variables.<br>
<br>
You can use the <tt>-e</tt> command-line option<br>
to execute code from the command line.<br>
<br>
<br>
HTH,<br>
<br>
Gerald<br>
</div>
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</blockquote>
</div>
</blockquote>
<br>
</div>
</blockquote>
</div>
</blockquote>
<br>
<br>
<pre cols="72">--
Juan Vuletich
<a href="http://cuis.st" target="_blank">cuis.st</a>
<a href="http://github.com/jvuletich" target="_blank">github.com/jvuletich</a>
<a href="http://researchgate.net/profile/Juan-Vuletich" target="_blank">researchgate.net/profile/Juan-Vuletich</a>
<a href="http://independent.academia.edu/JuanVuletich" target="_blank">independent.academia.edu/JuanVuletich</a>
<a href="http://patents.justia.com/inventor/juan-manuel-vuletich" target="_blank">patents.justia.com/inventor/juan-manuel-vuletich</a>
<a href="http://linkedin.com/in/juan-vuletich-75611b3" target="_blank">linkedin.com/in/juan-vuletich-75611b3</a>
<a href="http://twitter.com/JuanVuletich" target="_blank">twitter.com/JuanVuletich</a></pre>
</div>
</blockquote></div>