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</o:shapelayout></xml><![endif]--></head><body lang=DE link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks for your advice .. that's what I was looking for;)<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Makes sense, I'll stick to your advice, kick the subclassing approach and the stuff with the reordering version rcall().<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>That leaves "partial" and "lambda"<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> # Option 1 : prints 31<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> d2 = self.call("square", 6).addCallback(lambda res: self.call("sub", res, 5)).addCallback(self.show)<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> # Option 3 : prints -31<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> d4 = self.call("square", 6).addCallback(partial(self.call, "sub", 5)).addCallback(self.show)<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Lambda is the most general, since it can insert the previous deferred's result anywhere in the next call.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Partial only simulates append result to end of args of next call.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>But lambda is also most verbose.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I'll sleep one night and then see if I document and endorse both or only lambda.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Obviously, I can't hinder anyone using both. Built in stuff.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks again,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Tobias<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>Von:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> twisted-python-bounces@twistedmatrix.com [mailto:twisted-python-bounces@twistedmatrix.com] <b>Im Auftrag von </b>Glyph Lefkowitz<br><b>Gesendet:</b> Dienstag, 23. August 2011 20:30<br><b>An:</b> Twisted general discussion<br><b>Betreff:</b> Re: [Twisted-Python] RPC design questions<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Aug 23, 2011, at 10:37 AM, Tobias Oberstein wrote:<o:p></o:p></p></div><p class=MsoNormal><br><br><o:p></o:p></p><p class=MsoNormal><span class=apple-style-span><span style='font-size:13.5pt;font-family:"Courier New"'>class AutobahnDeferred(Deferred):</span></span><span style='font-size:13.5pt;font-family:"Courier New"'><br><span class=apple-style-span> def call(self, *args):</span><br><span class=apple-style-span> return self.addCallback(self.protocol.rcall, *args)</span><br><br><span class=apple-style-span>Pro:</span><span class=apple-tab-span> </span><span class=apple-style-span>most terse</span><br><span class=apple-style-span>Con:</span><span class=apple-tab-span> </span><span class=apple-style-span>only supports single callback no errback</span><br><br></span><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Con: subclassing in general is a bad idea. Subclassing Deferred is an even worse idea. What if Deferred one day gets a new method called 'call' that does something different? Your code would all break.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal><span class=apple-style-span><span style='font-family:"Courier New"'>Anything why I shouldn't do?</span></span><o:p></o:p></p></blockquote><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Providing three different ways to do the same thing just so that you can use different syntax depending on your mood is a recipe for making your code hard to read. Pick one style, stick to it as much as possible - consistency is more important than the benefits of any one particular style :).<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>(Except the subclassing one. Don't do that.)<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>-glyph<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></body></html>