On Tue, Mar 31, 2015 at 8:05 PM, Clément Bera <bera.clem...@gmail.com> wrote:
> Hey Sean, > > Now to create a proxy you need to subclass ProtoObject and not nil. > > Yes, subclassing from nil was never a good idea. > This was changed years ago to avoid some issues. An example of issue that > existed: when you subclass nil, as > #doesNotUnderstand: is not implemented by default on your proxy, any proxy > created receiving a message would crash the VM if you had not overridded > #doesNotUnderstand:. Another example is that when you iterate over memory > using #nextObject, if the proxy does not answer it you can end with severe > VM crashes. In these examples I am talking about the expected VM behavior > and not about bugs. > > Marea (kind of extended Ghost proxies) proxies deal with object listing. If you load Marea code, see class side of #MARAbstractProxy (#allInstances, #allInstancesDo: etc). > So basically the purpose of ProtoObject was to limit the number of VM > crashes when playing with proxies / ProtoObjects, instead having a default > behavior for several messages such as #doesNotUnderstand: or nextObject. > > Note that the IDE support for ProtoObject is limited as ProtoObject API is > very restricted so it does not have methods such as #inspect, ... That's > also on purpose because Proxies may not implement introspection methods. > > Yes. Ghost proxies provided debugger facilities (printing, inspecting, debugging, exploring, etc) which could be dynamically either enabled or disabled. If enabled, you could debug proxies without intercepting the "debugging" methods. > > > > > 2015-03-31 14:53 GMT-07:00 Sean P. DeNigris <s...@clipperadams.com>: > > Denis Kudriashov wrote >> > http://smalltalkhub.com/#!/~CAR/Ghost/ or >> http://ss3.gemstone.com/ss/Ghost >> >> Thanks, Denis! I'll check it out. I'm not sure which repo either. >> Mariano's >> commits are all in both places, but there seems to be some parallel >> development after that... >> >> >> >> ----- >> Cheers, >> Sean >> -- >> View this message in context: >> http://forum.world.st/Proxies-Subclassing-nil-tp4816443p4816503.html >> Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >> >> > -- Mariano http://marianopeck.wordpress.com
