On Thu, Oct 17, 2019 at 12:02 PM Tobias Pape <Das.Linux at gmx.de> wrote:

>
> > On 17.10.2019, at 20:41, Jakob Reschke <forums.jakob at resfarm.de> wrote:
> >
> > Is it really wise to remove the previous scripts?
> >
> > Suppose I have versions 1, 2, and 3 and object state needs to be
> migrated differently between each of them. If one image still has 1 loaded
> and is updated directly to 3, it will miss the object state updates from 1
> to 2, or it not even be able to perform an adequate update from 2 to 3.
> >
> > Shouldn't the scripts rather be idempotent? If they must run again, but
> the code is the same, you could add a comment explaining the reason...
> >
> > Of course you can draw a line by declaring particular earlier versions
> as "unsupported".
>
> That's the point where you create a new update map as a checkpoint.
>

+1


>
> Best regards
>         -Tobias
>
> >
> >
> > Am Mo., 14. Okt. 2019 um 22:01 Uhr schrieb karl ramberg <
> karlramberg at gmail.com>:
> > So the comment on top of the preamble and post script could be something
> like code below. Could we make this comment show even in a previous made
> preamble/ post script so it is there as a reminder ?
> >
> > 'From Squeak5.3alpha of 14 October 2019 [latest update: #19114] on 14
> October 2019 at 9:53:39 pm'!
> >
> > !PackageInfo methodsFor: 'preamble/postscript' stamp: 'kfr 10/14/2019
> 21:52'!
> > postscriptDefault
> > ^  '"Below, add code to be run after the loading of this package.
> Postscript is only evaluated when it is different than previous version.
> That is why it is always best practice to remove its previous contents when
> editing it."'
> > ! !
> >
> > !PackageInfo methodsFor: 'preamble/postscript' stamp: 'kfr 10/14/2019
> 21:49'!
> > preambleDefault
> > ^ '"Below, add code to be run before the loading of this package.
> Preamble is only evaluated when it is
> > different than previous version. That is why it is always best practice
> to remove its previous contents when editing it."'
> > ! !
> >
> >
> > On Mon, Oct 14, 2019 at 9:31 PM Levente Uzonyi <leves at caesar.elte.hu>
> wrote:
> > These scripts, preamble and postscript are only evaluated when they are
> > different than their previous versions. That is why I always suggest
> > removing their contents when changing them.
> >
> > Levente
> >
> > On Mon, 14 Oct 2019, Marcel Taeumel wrote:
> >
> > > Well, it seems to be that a "preamble" in a package is not evaluated
> when updating the image. Is this a bug?
> > > ChangeSet preambles also don't seem to be prepared to store a script.
> Just a documentation string. Why is that? :-)
> > >
> > > Best,
> > > Marcel
> > >
> > >
> >
> >
> >
>
>
>
>

-- 
_,,,^..^,,,_
best, Eliot
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