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<div dir="ltr" class="gmail_attr">On 9 Dec 2020 at 14:40:13, Joachim Breitner <<a href="mailto:mail@joachim-breitner.de">mail@joachim-breitner.de</a>> wrote:<br></div>
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Hi,<br><br>Am Mittwoch, den 09.12.2020, 12:08 +0000 schrieb Simon Peyton Jones via<br>ghc-steering-committee:<br><blockquote type="cite"> I agree with this. Not having scoped type variables (in any form) is<br></blockquote><blockquote type="cite"> a huge blemish. The existing design may not be perfect, but it’s<br></blockquote><blockquote type="cite"> worked rather well for a long time.<br></blockquote><br>The same is true for ViewPatterns, which are even more harmless (clear<br>syntactic opt-in; no spooky effect at a distance when type signature<br>and definition are far apart).<br><br>There we argued that the fact that we don’t think it’s perfect, and<br>some wiki page with an alternative design exists, was enough to plea<br>against it.<br><br>Here, the situation seems equivalent (we know of better designs, namely<br>binding type variables on the LHS of the equation).<br><br>Can we justify why we go one way here and another way there? Is it<br>because ViewPatterns are just mere convenience, and ScopedTypeVariables<br>are absolutely needed for some things?<br></div></blockquote><div class="gmail_quote"><br></div><div class="gmail_quote">This is what I think at least (I also voted ‘yes’ for ViewPatterns, but I wouldn’t mind not having them). No ViewPatterns, I just need one extra ‘case’ to stay in GHC2021.</div><div class="gmail_quote"><br></div><div class="gmail_quote">Alejandro</div>
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