I do not like either the “virus” name. not just because is negative in a subjective way… also it hides what it does inside a fantasy name, and that IMO is negative to self discovery of the system.
I mean… a framework can have a fantasy name… but a class? A method name? (#infect:… come on!) I know is “cool", but if I read the code below, I have NO CLUE of what is going to happen, and that’s not good. Esteban > On 28 Jul 2016, at 12:33, Steven Costiou <steven.cost...@kloum.io> wrote: > > Hi, > > I think i am missing something. > > For example in the following code (took from the tests): > > | victim virus actual | > virus := GHObjectVirus behaviour: GHGhostBehaviourStub new. > > victim := 0@0 corner: 3@4. > virus infect: victim. > victim corner > > The evaluation is trapped by the send:to: method in the behavior (i've put a > halt there). However if i replace the "corner" message by an inspect of the > victim, and if i evaluate "self corner", then the message is processed > without going through the send:to: method of the behavior. It is not halted > and the victim responds immediately to the message. I have also tried to add > a new method in the Rectangle class that calls "self corner". When called in > the playground, my new message is trapped but not the "corner" sent to self. > > From what i understand it could be related to the behavior i use, but i don't > see what's missing. > > > Le 2016-07-28 11:35, Denis Kudriashov a écrit : > >> I think I not understood second part of "self problem" in this paper. But >> self sends are covered by virus as I described. >> >> 2016-07-28 11:30 GMT+02:00 Denis Kudriashov <dionisi...@gmail.com >> <mailto:dionisi...@gmail.com>>: >> Hi >> >> 2016-07-27 22:19 GMT+02:00 Steven Costiou <steven.cost...@kloum.io >> <mailto:steven.cost...@kloum.io>>: >> Hi, >> >> I use virus from Ghost to intercept messages sent to a given object and >> adapt methods behaviors for this particular object only. However it would >> seems that doing interception this way is subject to the "self problem" >> described in this paper from Stéphane (DUCASSE, Stéphane. Evaluating message >> passing control techniques in Smalltalk. JOURNAL OF OBJECT ORIENTED >> PROGRAMMING, 1999, vol. 12, p. 39-50). >> >> I understand i could do instance based adaptation using an other technique, >> but i wonder if there is any way with Ghost to deal with this "self problem" >> problem ? >> >> I think "self problem" is only related to classic proxies when objects stay >> behind them. But ObjectVirus is not proxy in this meaning. When you infect >> your object by virus it is not replaced by somebody else. It is same >> original instance but with overridden behaviour. That's why I call it virus >> without any relation to proxies. >> Any message to infected object is processed by your behaviour. All self >> sends are intercepted. But there are few exceptions: >> - special messages like ==,ifTrue/ifNil are not intercepted >> - meta messages are not intercepted. They processed by Ghost mechanics but >> they not passed to your behaviour. Meta messages defined by >> #currentMetaLevel of your behaviour. You could implement it like: >> >> YourGhostBehaviour>>currentMetaLevel >> ^GHMetaLevel empty >> >> Empty meta level means that all messages will be passed to your behaviour. >> There is also "GHMetaLevel standard" which is default one. It makes most of >> "tool messages" not interceptable. For example #printString, #class, >> #instVarAt: will be not intercepted. It's messages which are usually used by >> tools like inspector and debugger. >> Standard meta level simplifies debugging of new behaviours. If you make >> mistake somewhere standard messages will be not broken and you could debug >> error by tools. >>
