Hey,
I have a question concerning the behavior of Collections in Squeak. Recently I face a problem when trying to delete some elements from a set during a 'do:' message. Have a look at this sample method:
doFallForAllIn: aSet aSet do: [:block | block fall ifFalse: [aSet remove: block]]
It loops over a set of blocks and performs the fall message on each of them. If a block is not falling I don't want it to be in aSet after the function returned so I remove it from the set. Squeak doesn't seem to like that since some rather strange error now occures: If a block is removed from the set, the next block in the set will be left out from looping... sometimes. Nearly all the time it works as exspected, only sometimes a block is ignored. I couldn't find any pattern when this happens.
So my question is: Has anyone an explanation for this? Does the error occure because the way I'm doing it is fundamentally wrong? Or am I just overlooking something and it is possible to remove blocks from a collection while looping over it?
Thanks in advance!