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<DIV><SPAN class=894095704-22082001><FONT face=Arial color=#0000ff size=2>It's
nice to see LindaTalk surviving all these years, in one way or another...
:-)</FONT></SPAN></DIV>
<DIV><SPAN class=894095704-22082001><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=894095704-22082001><FONT face=Arial color=#0000ff
size=2>Hopefully I'll get around to doing more Squeak from now on, we'll see.
I'll then take a look at it ;-)</FONT></SPAN></DIV>
<DIV><SPAN class=894095704-22082001><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=894095704-22082001><FONT face=Arial color=#0000ff size=2>Keep
up the good work !!</FONT></SPAN></DIV>
<DIV><SPAN class=894095704-22082001><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=894095704-22082001><FONT face=Arial color=#0000ff
size=2>marcio</FONT></SPAN></DIV>
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<DIV class=OutlookMessageHeader><FONT face="Times New Roman"
size=2>-----Original Message-----<BR><B>From:</B>
squeak-dev-admin@lists.squeakfoundation.org
[mailto:squeak-dev-admin@lists.squeakfoundation.org]<B>On Behalf Of</B>
Withers, Robert<BR><B>Sent:</B> August 21, 2001 10:41 PM<BR><B>To:</B>
'squeak-dev@lists.squeakfoundation.org'<BR><B>Subject:</B> RE: [Modules]
Unloading and Conflicting Versions<BR><BR></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=409214302-22082001>That's where I saw it. Thanks, Marcio. By
the way, did you notice that LindaTalk is on the new Squeak CD? I have
many changes to it, mainly the EventTupleSpace and recursive tuple matching,
but it isn't quite ready. I can send it to you if you would
like.</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=409214302-22082001></SPAN></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=409214302-22082001>cheers,</SPAN></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><SPAN
class=409214302-22082001>Rob</SPAN></FONT></DIV>
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<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> Marcio Marchini
[mailto:marcio@bedarra.com]<BR><B>Sent:</B> Tuesday, August 21, 2001 2:55
PM<BR><B>To:</B> Withers, Robert;
squeak-dev@lists.squeakfoundation.org<BR><B>Cc:</B>
modsqueak@bluefish.se<BR><B>Subject:</B> RE: [Modules] Unloading and
Conflicting Versions<BR><BR></DIV></FONT>
<DIV><FONT face=Arial color=#0000ff size=2><A
href="http://swiki.squeakfoundation.org/squeakfoundation/31">http://swiki.squeakfoundation.org/squeakfoundation/31</A></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><SPAN class=705445418-21082001><FONT face=Arial color=#0000ff
size=2>marcio</FONT></SPAN></DIV>
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<DIV class=OutlookMessageHeader><FONT face="Times New Roman"
size=2>-----Original Message-----<BR><B>From:</B> Withers, Robert
[mailto:rwithers@quallaby.com]<BR><B>Sent:</B> August 21, 2001 2:21
PM<BR><B>To:</B> 'squeak-dev@lists.squeakfoundation.org'<BR><B>Cc:</B>
modsqueak@bluefish.se<BR><B>Subject:</B> RE: [Modules] Unloading and
Conflicting Versions<BR><BR></FONT></DIV>
<P><FONT size=2>Dave, could you please repost these links? I
couldn't find them in the squeak ML archives.</FONT> </P>
<P><FONT size=2>thank you,</FONT> <BR><FONT size=2>Rob</FONT> </P>
<P><FONT size=2>> -----Original Message-----</FONT> <BR><FONT
size=2>> From: Dave [<A
href="mailto:dave@bedarra.com">mailto:dave@bedarra.com</A>]</FONT>
<BR><FONT size=2>> Sent: Monday, August 20, 2001 9:06 PM</FONT>
<BR><FONT size=2>> To: Les Tyrrell</FONT> <BR><FONT size=2>> Cc:
squeak-dev@lists.squeakfoundation.org; modsqueak@bluefish.se</FONT>
<BR><FONT size=2>> Subject: Re: [Modules] Unloading and Conflicting
Versions</FONT> <BR><FONT size=2>> </FONT><BR><FONT size=2>>
</FONT><BR><FONT size=2>> </FONT><BR><FONT size=2>> </FONT><BR><FONT
size=2>> 1. The mechanism for unloading is indeed a good deal more
complex than</FONT> <BR><FONT size=2>> loading and was one of the
throny problems OTI had to address in</FONT> <BR><FONT size=2>>
building embedded Smalltalk and Java. </FONT><BR><FONT size=2>>
</FONT><BR><FONT size=2>> Perhaps the issue of unloading is something
to be deferred until after</FONT> <BR><FONT size=2>> the basic module
and component mechanisms are defined and tested? </FONT><BR><FONT
size=2>> </FONT><BR><FONT size=2>> 2. To my knowledge the only
existing system that supports current</FONT> <BR><FONT size=2>>
execution of multiple versions classes/methods is MS.NET with their</FONT>
<BR><FONT size=2>> assemblies. This itself gets problematic however if
you want to run</FONT> <BR><FONT size=2>> shared assemblies. I posted
the references earlier for those </FONT><BR><FONT size=2>>
interested</FONT> <BR><FONT size=2>> in the problem.
</FONT><BR><FONT size=2>> </FONT><BR><FONT size=2>> Regards,</FONT>
<BR><FONT size=2>> Dave</FONT> <BR><FONT size=2>> </FONT><BR><FONT
size=2>> </FONT><BR><FONT size=2>> Les Tyrrell wrote:</FONT>
<BR><FONT size=2>> > </FONT><BR><FONT size=2>> > -----
Original Message -----</FONT> <BR><FONT size=2>> > From: Dan Moniz
<dnm@pobox.com></FONT> <BR><FONT size=2>> > >
I'm imagining that when you file in a ChangeSet (let's </FONT><BR><FONT
size=2>> say Foo.cs)</FONT> <BR><FONT size=2>> > >
into your image (Bar.image), your image is writing out </FONT><BR><FONT
size=2>> information to</FONT> <BR><FONT size=2>> >
> it's Bar.changes file that reflect the things Foo.cs is
</FONT><BR><FONT size=2>> doing to your</FONT> <BR><FONT size=2>>
> > image. Then, to back out, you could use a currently
</FONT><BR><FONT size=2>> fictional "Undo"</FONT> <BR><FONT size=2>>
> > feature which would allow you to back up steps as
recorded in</FONT> <BR><FONT size=2>> > >
Bar.changes</FONT> <BR><FONT size=2>> > </FONT><BR><FONT size=2>>
> There are a few things that would need to be done when
</FONT><BR><FONT size=2>> unloading a module. For</FONT>
<BR><FONT size=2>> > one, you would like a rapid way of gc'ing or
otherwise </FONT><BR><FONT size=2>> mutating any instances</FONT>
<BR><FONT size=2>> > defined by that module. Then, you will
want a rapid way of </FONT><BR><FONT size=2>> removing the</FONT>
<BR><FONT size=2>> > definitions found in that module.
ChangeSets are no </FONT><BR><FONT size=2>> better, and no worse,
at</FONT> <BR><FONT size=2>> > doing this than any other
scheme. There is no need to </FONT><BR><FONT size=2>> iterate
over a change</FONT> <BR><FONT size=2>> > log- the ChangeSet already
has an accounting of what it has </FONT><BR><FONT size=2>>
modified. So would</FONT> <BR><FONT size=2>> > an OasisModule,
or a Collage Layer.</FONT> <BR><FONT size=2>> > </FONT><BR><FONT
size=2>> > However, while associating a ChangeSet with either a
</FONT><BR><FONT size=2>> Collage Layer or an</FONT> <BR><FONT
size=2>> > OasisModule seems reasonable to me, trying to warp
</FONT><BR><FONT size=2>> ChangeSet into becoming more</FONT> <BR><FONT
size=2>> > like these things does not seem reasonable.</FONT>
<BR><FONT size=2>> > </FONT><BR><FONT size=2>> >
> This may necessitate modifications to userland tools to
</FONT><BR><FONT size=2>> deal with</FONT> <BR><FONT size=2>>
> > .changes file, and perhaps some modification to the
information</FONT> <BR><FONT size=2>> > > and/or
format of information stored in .changes files, </FONT><BR><FONT
size=2>> but I don't</FONT> <BR><FONT size=2>> > >
think it would be too drastic and I don't think it </FONT><BR><FONT
size=2>> would have much</FONT> <BR><FONT size=2>> >
> with the implementation of ChangeSets themselves.</FONT> <BR><FONT
size=2>> > </FONT><BR><FONT size=2>> > What's wrong with the
idea of implementing the roles of a </FONT><BR><FONT size=2>>
Components and</FONT> <BR><FONT size=2>> > Modules? In Oasis,
a Module is a component that keeps </FONT><BR><FONT size=2>> track of
Shared Globals,</FONT> <BR><FONT size=2>> > Undeclared variables,
Pools, and a few other things. </FONT><BR><FONT size=2>>
ChangeSets don't do this.</FONT> <BR><FONT size=2>> >
</FONT><BR><FONT size=2>> > The role of a changeset is to keep track
of changes... the </FONT><BR><FONT size=2>> role of an</FONT> <BR><FONT
size=2>> > OasisModule is to act as a place in which those changes
</FONT><BR><FONT size=2>> take effect. These are</FONT> <BR><FONT
size=2>> > separate roles, so I would not reccomend mixing
them. </FONT><BR><FONT size=2>> ChangeSets are just fine</FONT>
<BR><FONT size=2>> > the way they are, at least in the sense of the
scoping of </FONT><BR><FONT size=2>> their responsibilities</FONT>
<BR><FONT size=2>> > to tracking changes, and no more.</FONT>
<BR><FONT size=2>> > </FONT><BR><FONT size=2>> > Using
ChangeSets as a means of identifying chunks of code </FONT><BR><FONT
size=2>> to turn into a package</FONT> <BR><FONT size=2>> > is
another issue, as far as I know there is nothing wrong with that.</FONT>
<BR><FONT size=2>> > </FONT><BR><FONT size=2>> > - les</FONT>
<BR><FONT size=2>> </FONT><BR><FONT size=2>>
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