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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:36.0pt">
Generally, I'm not in favour in proposals which split extensions though: we already have so many extensions. Are the reasons for this split strong enough? I haven't had time to dig into the details.<o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Arnaud, happily, you don’t have to dig very deep – just read the handful of posts following my recommendation.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">There seem to be two motivations.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l1 level1 lfo2"><span style="mso-fareast-language:EN-US">There really are two orthogonal extensions, one for r.x notation, and one for overloaded update. Iavor likes the first but not the second.
Neil likes both. Having separate extensions lets us experiment.<o:p></o:p></span></li></ol>
<p class="MsoListParagraph"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l1 level1 lfo2"><span style="mso-fareast-language:EN-US">You suggest that changing the definition of RecordDotSyntax in a subsequent release, e.g. by subsequently making it imply NoFieldSelectors,
would be fine. But it certainly imposes pain – some programs would stop compiling. The approach offered by this proposal avoids that problem.<o:p></o:p></span></li></ol>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Yes, there are lots of extensions surrounding records: NoFieldSelectors, DuplicateRecordFields, NamedFieldPuns, DisambiguateRecordFields, RecordWildCards. It may not be pretty to divide things up
so fine, but it’s not new.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">If there are alternative suggestions, let’s hear them.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> ghc-steering-committee <ghc-steering-committee-bounces@haskell.org>
<b>On Behalf Of </b>Spiwack, Arnaud<br>
<b>Sent:</b> 26 February 2021 22:33<br>
<b>To:</b> Iavor Diatchki <iavor.diatchki@gmail.com><br>
<b>Cc:</b> ghc-steering-committee <ghc-steering-committee@haskell.org><br>
<b>Subject:</b> Re: [ghc-steering-committee] Modification to record dot syntax propsal<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<o:p> </o:p></p>
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I do think that reusing the record update syntax for the overloaded monomorphic update is a mistake---it is not something I had noticed during our original discussion.<o:p></o:p></p>
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<o:p> </o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:0cm">
This is the one reason I can see for cutting this extension in smaller pieces. But, then again, -XOverloadedRecordUpdate would be a fork-like extension.<o:p></o:p></p>
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<o:p> </o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:0cm">
Generally, I'm not in favour in proposals which split extensions though: we already have so many extensions. Are the reasons for this split strong enough? I haven't had time to dig into the details.<o:p></o:p></p>
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<o:p> </o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:0cm">
I'm not sure that not having the design of the proposal quite finalised is a good reason, extensions mutate in their first iterations, I don't think that it's a problem.<o:p></o:p></p>
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