[Squeakland] re: Error loading project with plugin.

[Scott Wallace]

On Apr 22, 2008, at 4:08 PM, Jerome Peace wrote:

> [Squeakland] Error loading project with plugin.
> or what do you do with MorphicExtentionPlus when the class isn't  
> there?
>
> Hi Scott, (Hi Yoandy)
>
> I ran into this problem with the olpc image.
>
> On a lucky guess I answered the question about which "modern" class  
> to use to replace "MorphicExtentionPlus"
> with  "MorphicExtention" (the old class).
> This, to my surprise, worked.
> So I took a closer look and saw that so far the ..Plus extentions  
> purpose
> was to optimize layout time by making ivars out of properties in the  
> otherProperties dictionary.
> By using the old extention the optimization is lost but nothing is  
> really broken.
>
> Maybe someone can formalize this workaround?



While it's true that some projects created in olpc-based images can  
indeed be successfully loaded into an old Squeakland plug-image using  
the workaround Jerome discovered, most projects will encounter  
numerous other roadblocks of a similar nature, none of them as simply  
worked around as in the MorphExtensionPlus case.  Every object present  
in the project which belongs to a class added or changed during the  
past year and a half of intensive development of the etoys system on  
the olpc will cause difficulties when you try to load it into the  
older image.

-- Scott