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<p>> <span>Question is, should X class>>canUnderstand: be overwritten, too?</span></p>
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<p><span>This would not be possible in my example, would it? Each json object understands different keys ... This is also why I favor #respondsTo: over #canUnderstand: in general.</span></p>
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<p>Best,</p>
<p>Christoph</p>
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<div id="x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>Von:</b> Squeak-dev <squeak-dev-bounces@lists.squeakfoundation.org> im Auftrag von Tobias Pape <Das.Linux@gmx.de><br>
<b>Gesendet:</b> Freitag, 31. Januar 2020 10:30:20<br>
<b>An:</b> The general-purpose Squeak developers list<br>
<b>Betreff:</b> Re: [squeak-dev] Should you override #doesNotUnderstand: and #respondsTo: together?</font>
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> On 31.01.2020, at 10:14, Thiede, Christoph <Christoph.Thiede@student.hpi.uni-potsdam.de> wrote:<br>
> <br>
> Hi all,<br>
> <br>
> just struggled over the fact that Json objects provide access to their keys via #doesNotUnderstand:, but they do not override #respondsTo:. Example:<br>
> <br>
> json := Json readFromString: '{"foo": 42}'.<br>
> json foo. "42"<br>
> json respondsTo: #foo. "false"<br>
> <br>
> Question: Is this discrepancy indeed desired behavior? Or should we rather always try to override #doesNotUnderstand: and #respondsTo: together?<br>
<br>
This is actually done very seldom, IIRC.<br>
But maybe a good pattern, tho. Question is, should X class>>canUnderstand: be overwritten, too?<br>
<br>
Best regards<br>
-Tobias<br>
<br>
> <br>
> Best,<br>
> Christoph<br>
<br>
<br>
<br>
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