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--></style></head><body lang=EN-US link=blue vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Agree with Paul. The PEP is well thought out and well presented, but I really don’t think we need this in Python (and I say this as someone who uses it regularly in C/C#).</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>-1 on the idea; no disrespect intended toward to people who did a lot of work on it.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Top-posted from my Windows phone</p><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='border:none;padding:0in'><b>From: </b><a href="mailto:p.f.moore@gmail.com">Paul Moore</a><br><b>Sent: </b>Tuesday, April 17, 2018 6:31<br><b>To: </b><a href="mailto:mertz@gnosis.cx">David Mertz</a><br><b>Cc: </b><a href="mailto:ncoghlan@gmail.com">Nick Coghlan</a>; <a href="mailto:python-dev@python.org">Python-Dev</a><br><b>Subject: </b>Re: [Python-Dev] PEP 572: Assignment Expressions</p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>On 17 April 2018 at 14:07, Paul Moore <p.f.moore@gmail.com> wrote:</p><p class=MsoNormal>> On 17 April 2018 at 14:01, David Mertz <mertz@gnosis.cx> wrote:</p><p class=MsoNormal>>> Strongly agree with Nick that only simple name targets should be permitted</p><p class=MsoNormal>>> (at least initially). NONE of the motivating cases use more complex targets,</p><p class=MsoNormal>>> and allowing them encourages obscurity and code golf.</p><p class=MsoNormal>><o:p> </o:p></p><p class=MsoNormal>> I also agree. Originally I would have said why not allow them, it's a</p><p class=MsoNormal>> potentially useful generalisation. But Nick's examples pretty clearly</p><p class=MsoNormal>> demonstrate that there are a lot of unclear edge cases involved, and</p><p class=MsoNormal>> even though "prevent people writing ugly code" is explicitly stated as</p><p class=MsoNormal>> a non-goal in the PEP, that doesn't mean it's OK to allow an obvious</p><p class=MsoNormal>> bug magnet with no clear use cases.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I should also point out that I remain -0 on this proposal (I'd already</p><p class=MsoNormal>said this on python-ideas, but I should probably repeat it here). For</p><p class=MsoNormal>me, the use cases are mostly marginal, and the major disadvantage is</p><p class=MsoNormal>in having two forms of assignment. Explaining to a beginner why we use</p><p class=MsoNormal>a := b in an expression, but a = b in a statement is going to be a</p><p class=MsoNormal>challenge.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The fact that the PEP needs a section covering all the style guide</p><p class=MsoNormal>warnings we feel are needed seems like it's a warning bell, too.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Paul</p><p class=MsoNormal>_______________________________________________</p><p class=MsoNormal>Python-Dev mailing list</p><p class=MsoNormal>Python-Dev@python.org</p><p class=MsoNormal>https://mail.python.org/mailman/listinfo/python-dev</p><p class=MsoNormal>Unsubscribe: https://mail.python.org/mailman/options/python-dev/steve.dower%40python.org</p><p class=MsoNormal><o:p> </o:p></p></div></body></html>