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.

Hey Sean, Now to create a proxy you need to subclass ProtoObject and not nil. 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. 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. 2015-03-31 14:53 GMT-07:00 Sean P. DeNigris <sean@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 spent a couple of years on it so... Le 31/3/15 21:37, Denis Kudriashov a écrit :

Hi if you want to build proxy look at Ghost library from Mariano Martinez I not know right repository. Maybe this:http://smalltalkhub.com/#!/~CAR/Ghost/ <http://smalltalkhub.com/#%21/%7ECAR/Ghost/> or http://ss3.gemstone.com/ss/Ghost

2015-03-31 19:51 GMT+03:00 Sean P. DeNigris <sean@clipperadams.com <mailto:sean@clipperadams.com>>:

From "Design Patterns" pg. 215:

You can make[8] generic proxies in Smalltalk by defining classes whose superclass is nil and defining the doesNotUnderstand: method to handle messages.

[8] Almost all classes ultimately have Object as their superclass. Hence this is the same as saying "defining a class that doesn't have Object as its superclass."

but in Pharo: nil subclass: #MyProxy instanceVariableNames: '' classVariableNames: '' category: '' -> MessageNotUnderstood: receiver of "subclass:instanceVariableNames:classVariableNames:category:" is nil

----- Cheers, Sean -- View this message in context: http://forum.world.st/Proxies-Subclassing-nil-tp4816443.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

On Wed, Apr 1, 2015 at 4:29 AM, Luc Fabresse <luc.fabresse@gmail.com> wrote:

and the latest repo is: http://smalltalkhub.com/#!/~CAR/Ghost but it has not diverged too much from the old one yet.

Luc...something that would be super super cool is to take the proxies I implemented for Marea and adapt them as custom Ghost proxies. Because the idea of Ghost was mostly the design, not the code itself. The code was very very little. So in Marea proxies you can see how I: 1) Created a few different proxies for different purposes. For example, I created special proxies for classes and metaclasses. And each of them implements custom messages to avoid unnecessary interception (for example, MARMetaclassProxy implements #isMeta answering true. Both, proxy for Class and Metaclass implement: isKindOf: aClass ^ (aClass == Class) ifTrue: [ true ] ifFalse: [ super isKindOf: aClass ] "would be intercepted" and so on.... So basically....you are able to implement custom proxies and implement custom messages so that you avoid intercepting them. 2) In Marea, I have multiple proxies that store the information differently. So for example, Marea proxies needed a graph id and a "position" (an integer). If both were small enough, I was doing a bitShift and storing them in a super compact proxy class that would have only one small integer. So....what I want to say is that while ghost code is OK, the most interesting usage and development of those proxies is in Marea, in the category 'Marea-Proxies'.

#Luc

2015-04-01 8:29 GMT+02:00 stepharo <stepharo@free.fr>:

...

Mariano spent a couple of years on it so...

Le 31/3/15 21:37, Denis Kudriashov a écrit :

Hi if you want to build proxy look at Ghost library from Mariano Martinez I not know right repository. Maybe this: http://smalltalkhub.com/#!/~CAR/Ghost/ or http://ss3.gemstone.com/ss/Ghost

2015-03-31 19:51 GMT+03:00 Sean P. DeNigris <sean@clipperadams.com>:

...

From "Design Patterns" pg. 215:

You can make[8] generic proxies in Smalltalk by defining classes whose superclass is nil and defining the doesNotUnderstand: method to handle messages.

[8] Almost all classes ultimately have Object as their superclass. Hence this is the same as saying "defining a class that doesn't have Object as its superclass."

but in Pharo: nil subclass: #MyProxy instanceVariableNames: '' classVariableNames: '' category: '' -> MessageNotUnderstood: receiver of "subclass:instanceVariableNames:classVariableNames:category:" is nil

----- Cheers, Sean -- View this message in context: http://forum.world.st/Proxies-Subclassing-nil-tp4816443.html Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

-- Mariano http://marianopeck.wordpress.com