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<p class="MsoNormal" style="margin-left:36.0pt">Most of the criticisms are around the fact the the current manifestation is not ideal, something I agree with. I would say in this case we should not let perfect be the enemy of good: if during the years, once
types in patterns or Dependent Haskell extensions require this, the scoping mechanism needs to change, we can do it. But as of now, ScopedTypeVariables is a very important piece in the flavour of Haskell in main usage (given its mainstream acceptance).<o:p></o:p></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">I agree with this. Not having scoped type variables (in any form) is a huge blemish. The existing design may not be perfect, but it’s worked rather well for a long time.<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>Alejandro Serrano Mena<br>
<b>Sent:</b> 07 December 2020 20:26<br>
<b>To:</b> ghc-steering-committee@haskell.org<br>
<b>Subject:</b> [ghc-steering-committee] GHC2021: a final plea for ScopedTypeVariables<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Dear all,<o:p></o:p></p>
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<p class="MsoNormal">I’ll try once again (this is the last one, I’ll promise) to convince the Committee of including ScopedTypeVariables as part of GHC2021. It has been with us for a long time — so their problems seem well understood — and the community seems
to want it as part of this new “language version” — which means that people are really using it.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Most of the criticisms are around the fact the the current manifestation is not ideal, something I agree with. I would say in this case we should not let perfect be the enemy of good: if during the years, once types in patterns or Dependent
Haskell extensions require this, the scoping mechanism needs to change, we can do it. But as of now, ScopedTypeVariables is a very important piece in the flavour of Haskell in main usage (given its mainstream acceptance).<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">forall (member :: Committee). Regards -> member<o:p></o:p></p>
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