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<div>Hi Eliot.</div><div><br></div>> <span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px">P.S. I may have the selector wrong, but there is a mirror identical. Whatever the selector is, I meant that.</span><div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px"><br></span></div><div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px">It is Context >> #object:eqeq:.</span></div><div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px"><br></span></div><div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px">Best,</span></div><div><span style="font-family: Arial, Helvetica, sans-serif;font-size: 13px">Marcel</span></div><div class="mb_sig"></div><blockquote class="history_container" type="cite" style="border-left-style:solid;border-width:1px; margin-top:20px; margin-left:0px;padding-left:10px;">
<p style="color: #AAAAAA; margin-top: 10px;">Am 16.02.2020 02:59:55 schrieb Eliot Miranda <eliot.miranda@gmail.com>:</p><div style="font-family:Arial,Helvetica,sans-serif"><div dir="ltr"><br></div><div dir="ltr"><blockquote type="cite">On Feb 15, 2020, at 6:59 AM, Thiede, Christoph <Christoph.Thiede@student.hpi.uni-potsdam.de> wrote:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr">
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<p>> <span style="font-size: 12pt">Example:</span></p>
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<div>> anObject := (MyDecorator on: anotherObject)</div>
<div>> doSomething;</div>
<div>> yourself.</div>
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<div>> I would like that anObject is the decorator and not anotherObject at the end.</div>
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<div>Marcel told me the following tip for this scenario, which sounds quite interesting to me:</div>
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<div>doesNotUnderstand: aMessage</div>
<div><span style="font-size: 12pt;white-space: pre"></span><span style="font-size: 12pt">| result |</span><br>
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<div><span style="white-space:pre"></span>result := aMessage sendTo: target.</div>
<div><span style="white-space:pre"></span>^<span style="font-size: 12pt"> target == result</span></div></div></div></div></blockquote><blockquote type="cite"><div dir="ltr"><div id="divtagdefaultwrapper" dir="ltr" style="font-size: 12pt;font-family: Calibri, Helvetica, sans-serif"><div><span style="white-space: pre;"></span>ifTrue: [self]</div><div><span style="white-space: pre;"></span>ifFalse: [result]</div></div></div></blockquote><div><br></div>+1. Everyone writing proxies should be aware of this. BUT!! !Ot should be written as<div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 12pt"><br></span></div><div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 12pt">^</span><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 12pt"> (thisContext object: target identical: result)</span></div><div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 12pt"> ifTrue: [self]</span></div><div><span style="font-family: Calibri, Helvetica, sans-serif;font-size: 12pt"> ifFalse: [result]</span><div><br></div><div>to avoid sending a message if #== is a true message send (which is what we’re intending to arrange).</div><div><br></div><div>P.S. I may have the selector wrong, but there is a mirror identical. Whatever the selector is, I meant that.</div><div><br><blockquote type="cite"><div dir="ltr"><div id="divtagdefaultwrapper" style="font-size: 12pt;color: #000000;font-family: Calibri,Helvetica,sans-serif" dir="ltr"><div>
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<div>:-)</div>
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<div id="divRplyFwdMsg" dir="ltr"><span style="font-family: Calibri, sans-serif;color: #000000"><b>Von:</b> Squeak-dev <squeak-dev-bounces@lists.squeakfoundation.org> im Auftrag von Jakob Reschke <forums.jakob@resfarm.de><br>
<b>Gesendet:</b> Samstag, 15. Februar 2020 09:28:58<br>
<b>An:</b> The general-purpose Squeak developers list<br>
<b>Betreff:</b> Re: [squeak-dev] [Bug & design issue] Messages understood or not understood by ProtoObject</span>
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<div dir="ltr">Thanks Eliot, I understood that for the inspector use case, but my thought about #yourself was rather the following:
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<div>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.</div>
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<div>Example:</div>
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<div> anObject := (MyDecorator on: anotherObject)</div>
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<div> yourself.</div>
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<div>I would like that anObject is the decorator and not anotherObject at the end.</div>
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<div dir="ltr" class="gmail_attr">Am Fr., 14. Feb. 2020 um 22:39 Uhr schrieb Eliot Miranda <<a href="mailto:eliot.miranda@gmail.com">eliot.miranda@gmail.com</a>>:<br>
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<div dir="ltr">Hi Jakob,</div>
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<div dir="ltr" class="gmail_attr">On Fri, Feb 14, 2020 at 1:14 PM Jakob Reschke <<a href="mailto:forums.jakob@resfarm.de" target="_blank">forums.jakob@resfarm.de</a>> wrote:<br>
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<div dir="ltr">Am Fr., 14. Feb. 2020 um 19:42 Uhr schrieb Eliot Miranda <<a href="mailto:eliot.miranda@gmail.com" target="_blank">eliot.miranda@gmail.com</a>>:<br>
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<div dir="auto">Hi Christoph,
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<blockquote type="cite">On Feb 14, 2020, at 9:51 AM, Thiede, Christoph <<a href="mailto:Christoph.Thiede@student.hpi.uni-potsdam.de" target="_blank">Christoph.Thiede@student.hpi.uni-potsdam.de</a>> wrote:</blockquote>
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<div>> <span style="font-size: 12pt">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:</span>
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<div>I like and do agree to your vision for tidying up ProtoObject!</div>
<div>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:</div>
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<div>(MetaDecorator on: aMorph) class "--> Morph"</div>
<div><span style="font-family: Calibri,Helvetica,sans-serif,EmojiFont,"Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols;font-size: 16px">(MetaDecorator on: aProxy</span><span style="font-family: Calibri,Helvetica,sans-serif,EmojiFont,"Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols;font-size: 16px">)
class "--> Proxy"</span><br>
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<div><span style="font-family: Calibri,Helvetica,sans-serif,EmojiFont,"Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols;font-size: 16px"><span style="font-family: Calibri,Helvetica,sans-serif,EmojiFont,"Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols;font-size: 16px">(MetaDecorator
on: aProxy</span><span style="font-family: Calibri,Helvetica,sans-serif,EmojiFont,"Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols;font-size: 16px">) instVarsInclude: 'target' "--> true"</span><br>
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<span style="font-family: Calibri,Helvetica,sans-serif,EmojiFont,"Apple Color Emoji","Segoe UI Emoji",NotoColorEmoji,"Segoe UI Symbol","Android Emoji",EmojiSymbols;font-size: 16px;color: rgb(0,0,0)">Sounds good.</span><br>
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<div>If inspectors et al would use this, my decorators might not have to carry the following collection of methods/copies:</div>
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<div>asExplorerString basicInspect basicSize class instVarAt: instVarAt:put: perform: perform:withArguments: primitiveFailed printString printStringLimitedTo: respondsTo: xxxClass<br>
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<div>If DataStream et al did, add the following:</div>
<div>readDataFrom:size: storeDataOn: <br>
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<div>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.</div>
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typically use of the mirror protocol, at its most basic, looks like<br clear="all">
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<div> thisContext object: foo instVarAt: index</div>
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<div>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? </div>
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<div>_,,,^..^,,,_<br>
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<div>best, Eliot</div>
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