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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">I’m afraid I didn’t understand the issue in the link below. It speaks of “querying the type”, but I’m not sure what that means. A GHCi session perhaps? Does this
relate to the way GHCi displays types?<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">I’m a bit lost. A from-the-beginning example, showing steps and what the unexpected behaviour is would be helpful (to me anyway)<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"> ghc-devs [mailto:ghc-devs-bounces@haskell.org]
<b>On Behalf Of </b>Christopher Done<br>
<b>Sent:</b> 19 October 2016 12:46<br>
<b>To:</b> ghc-devs@haskell.org<br>
<b>Subject:</b> How to best display type variables with the same name<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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We've encountered a problem in Intero which is that when inspecting types of expressions and patterns, sometimes it happens that the type, when pretty printing, yields variables of the same name but which have different provenance.<o:p></o:p></p>
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<o:p> </o:p></p>
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Here's a summary of the issue:<o:p></o:p></p>
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<o:p> </o:p></p>
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<a href="https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fcommercialhaskell%2Fintero%2Fissues%2F280%23issuecomment-254784904&data=02%7C01%7Csimonpj%40microsoft.com%7C58538b7f7532497970c708d3f8158e45%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636124743872989785&sdata=2AkHss5Io%2BHqJjF8CtFwSErBuUca6N2gJ3DELC03nFY%3D&reserved=0" target="_blank">https://github.com/commercialhaskell/intero/issues/280#issuecomment-254784904</a><o:p></o:p></p>
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<o:p> </o:p></p>
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And a strawman proposal of how it could be solved:<o:p></o:p></p>
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<o:p> </o:p></p>
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<a href="https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fcommercialhaskell%2Fintero%2Fissues%2F280%23issuecomment-254787927&data=02%7C01%7Csimonpj%40microsoft.com%7C58538b7f7532497970c708d3f8158e45%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636124743872989785&sdata=ev%2FJQg4xKrZVyi0uP9PxS756t41IO4%2BoI0AlJoT9F7U%3D&reserved=0" target="_blank">https://github.com/commercialhaskell/intero/issues/280#issuecomment-254787927</a><o:p></o:p></p>
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<o:p> </o:p></p>
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What do you think? <o:p></o:p></p>
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<o:p> </o:p></p>
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Also, if I were to implement the strawman proposal, is it possible to recover from a `tyvar :: Type` its original quantification/its "forall"? I've had a look through the API briefly and it looks like a _maybe_.<o:p></o:p></p>
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<o:p> </o:p></p>
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Ciao!<o:p></o:p></p>
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