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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:36.0pt">
I’ve forgotten the state of your type-level error messages work.  How’s it going?<o:p></o:p></p>
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I think we should try to add it to 8.0.1.  The current status is that the idea is implemented on a branch.  Then, there were some comments and suggestions that maybe we should do things in a different way, implementation wise.  I haven't had a chance to look
 into these in detail, or implement them, and as far as I know nobody else has stepped up to make the changes.  So we could simply go with the current version, and if for some reason we want to change the implementation we could do it later, as I don't think
 the API will be affected in any way.    When do the changes need to happen by, so that it makes it in 8.0?   I have been a bit busy, but I could probably find some time to make whatever changes are required for this to be merged.<o:p></o:p></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">OK good!  In that case<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-family:Symbol;mso-fareast-language:EN-US"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">        
</span></span></span><![endif]><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Add it to the hoped-for features in the GHC 8.01. status page<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-family:Symbol;mso-fareast-language:EN-US"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">        
</span></span></span><![endif]><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Write a wiki page with a specification<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-family:Symbol;mso-fareast-language:EN-US"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">        
</span></span></span><![endif]><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Announce the proposal and seek feedback<o:p></o:p></span></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="font-family:Symbol;mso-fareast-language:EN-US"><span style="mso-list:Ignore">·<span style="font:7.0pt "Times New Roman"">        
</span></span></span><![endif]><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Meanwhile make sure the branch reflects what you want to be in it<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">If you don’t have time, well, no harm done… any progress you make on the above will still be useful.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Iavor Diatchki [mailto:iavor.diatchki@gmail.com]
<br>
<b>Sent:</b> 22 October 2015 17:42<br>
<b>To:</b> Simon Peyton Jones<br>
<b>Cc:</b> Augustsson, Lennart<br>
<b>Subject:</b> Re: Type-level error messages<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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Hello,<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 think we should try to add it to 8.0.1.  The current status is that the idea is implemented on a branch.  Then, there were some comments and suggestions that maybe we should do things in a different way, implementation wise.  I haven't had a chance to look
 into these in detail, or implement them, and as far as I know nobody else has stepped up to make the changes.  So we could simply go with the current version, and if for some reason we want to change the implementation we could do it later, as I don't think
 the API will be affected in any way.    When do the changes need to happen by, so that it makes it in 8.0?   I have been a bit busy, but I could probably find some time to make whatever changes are required for this to be merged.<o:p></o:p></p>
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<o:p> </o:p></p>
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-Iavor<o:p></o:p></p>
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<o:p> </o:p></p>
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<o:p> </o:p></p>
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<o:p> </o:p></p>
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<o:p> </o:p></p>
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<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">
On Thu, Oct 22, 2015 at 3:47 AM, Simon Peyton Jones <<a href="mailto:simonpj@microsoft.com" target="_blank">simonpj@microsoft.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Iavor<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I’ve forgotten the state of your type-level error messages work.  How’s it going?<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">It’s not mentioned on
<a href="https://ghc.haskell.org/trac/ghc/wiki/Status/GHC-8.0.1" target="_blank">
https://ghc.haskell.org/trac/ghc/wiki/Status/GHC-8.0.1</a>: shouldn’t it be?<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="color:#888888">Simon<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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