> On Feb 15, 2020, at 6:59 AM, Thiede, Christoph <Christoph.Thiede at student.hpi.uni-potsdam.de> wrote:
> 
> 
> > Example:
> 
> > 
> >    anObject := (MyDecorator on: anotherObject)
> >       doSomething;
> >       yourself.
> > 
> > I would like that anObject is the decorator and not anotherObject at the end.
> 
> Marcel told me the following tip for this scenario, which sounds quite interesting to me:
> 
> doesNotUnderstand: aMessage
> | result |
> result := aMessage sendTo: target.
> ^ target == result
> ifTrue: [self]
> ifFalse: [result]

+1.  Everyone writing proxies should be aware of this.  BUT!! !Ot should be written as

^ (thisContext object: target identical: result)
       ifTrue: [self]
       ifFalse: [result]

to avoid sending a message if #== is a true message send (which is what we’re intending to arrange).

P.S. I may have the selector wrong, but there is a mirror identical.  Whatever the selector is, I meant that.

> :-)
> Von: Squeak-dev <squeak-dev-bounces at lists.squeakfoundation.org> im Auftrag von Jakob Reschke <forums.jakob at resfarm.de>
> Gesendet: Samstag, 15. Februar 2020 09:28:58
> An: The general-purpose Squeak developers list
> Betreff: Re: [squeak-dev] [Bug & design issue] Messages understood or not understood by ProtoObject
>  
> Thanks Eliot, I understood that for the inspector use case, but my thought about #yourself was rather the following:
> 
> If I pass the decorator around and some domain code (not in Inspector or similar) uses the decorator in a cascade with yourself at the end, I do not want the result to be the undecorated object.
> 
> Example:
> 
>     anObject := (MyDecorator on: anotherObject)
>        doSomething;
>        yourself.
> 
> I would like that anObject is the decorator and not anotherObject at the end.
> 
>> Am Fr., 14. Feb. 2020 um 22:39 Uhr schrieb Eliot Miranda <eliot.miranda at gmail.com>:
>> Hi Jakob,
>> 
>>> On Fri, Feb 14, 2020 at 1:14 PM Jakob Reschke <forums.jakob at resfarm.de> wrote:
>>> Am Fr., 14. Feb. 2020 um 19:42 Uhr schrieb Eliot Miranda <eliot.miranda at gmail.com>:
>>>> Hi Christoph,
>>>> 
>>>>> On Feb 14, 2020, at 9:51 AM, Thiede, Christoph <Christoph.Thiede at student.hpi.uni-potsdam.de> wrote:
>>>> 
>>>>> 
>>>>> > There is a good solution to this.  Low-level Inspectors *should not* use instVarAt: et al.  Instead they should access object intervals via “the mirror protocol”, see the methods in Context, #object:instVarAt:[put:] #object:at:[put:] #objectClass:
>>>>> 
>>>>> I like and do agree to your vision for tidying up ProtoObject!
>>>>> Maybe we could also consider some "MetaDecorator" that inherits from ProtoObject and implements #class, #instVarAt: etc. for arbitrary targets? This might simplify the access to the mirror protocol, and it would be a bit more object-oriented:
>>>>> 
>>>>> (MetaDecorator on: aMorph) class "--> Morph"
>>>>> (MetaDecorator on: aProxy) class "--> Proxy"
>>>>> (MetaDecorator on: aProxy) instVarsInclude: 'target' "--> true"
>>>>> 
>>>> Sounds good.
>>>>> 
>>> If inspectors et al would use this, my decorators might not have to carry the following collection of methods/copies:
>>> 
>>> asExplorerString basicInspect basicSize class instVarAt: instVarAt:put: perform: perform:withArguments: primitiveFailed printString printStringLimitedTo: respondsTo: xxxClass
>>> 
>>> If DataStream et al did, add the following:
>>> readDataFrom:size: storeDataOn: 
>>> 
>>> I'm not sure how to generally handle #yourself. I have this in my decorators as well because I don't want to undecorate when the decorator receives it.
>>> 
>> 
>> 
>> typically use of the mirror protocol, at its most basic, looks like
>> 
>>     thisContext object: foo instVarAt: index
>> 
>> so #yourself is handled by ending the cascade early, and answering the object (foo in the above).  Yes that's a tedious refactor, but straightforward, no?  
>> -- 
>> _,,,^..^,,,_
>> best, Eliot
>> 
> 
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