[squeak-dev] Re: immutibility

Eliot Miranda eliot.miranda at gmail.com
Thu Mar 18 16:19:21 UTC 2010


On Thu, Mar 18, 2010 at 8:17 AM, James Foster <Smalltalk at jgfoster.net>wrote:

> On Mar 17, 2010, at 11:28 PM, Igor Stasenko wrote:
>
> > the above is an example when object, recorded as an immutable one,
> > then mutated outside a DB transaction. So db can't capture the attempt
> > to modify it. What GemStone doing to handle this?
>
> Actually, GemStone traps object modification at the byte-code level in the
> VM so does not rely on immutability to be informed of a modification.
>

Not preferrentially.  It used to do that, but it is a problematic approach.
 The preferred implementation is above VM-supported per-object immutability.
 We've recently discussed this topic, I think on the Pharo list.  Martin
McClure of GemStone wrote excellent posts describing the implementations,
their trade offs, and the higher levels of the framework which support
installing managers for the immutability exception that supports multiple
frameworks using immutability concurrently.


> James
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.squeakfoundation.org/pipermail/squeak-dev/attachments/20100318/72b4636e/attachment.htm


More information about the Squeak-dev mailing list