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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">
Simon, my reasoning here is that holes are the only place GHC will mention relevant bindings. I'd definitely prefer to put all of the relevant local bindings in scope for _every_ HsVar, but that seemed less amenable to being merged :)<o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">I didn’t explain myself well enough. No need to merge anything.
<b>Your tooling</b> can accumulate these bindings as it walks the tree -- no need for GHC to do anything. Eg<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">myTooling env (HsLam (HsVar x) e) = myTooling (extend env x) e<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">myTooling env <expr of interest> = <do something with expr of interest, knowing all in-scope binding s in env><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>
<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"> Sandy Maguire <sandy@sandymaguire.me>
<br>
<b>Sent:</b> 29 August 2019 06:37<br>
<b>To:</b> Simon Peyton Jones <simonpj@microsoft.com><br>
<b>Cc:</b> Sandy Maguire <sandy@sandymaguire.me>; ghc-devs@haskell.org<br>
<b>Subject:</b> Re: Getting a hole's relevant local binds?<o:p></o:p></span></p>
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<p class="MsoNormal"><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">
Simon, my reasoning here is that holes are the only place GHC will mention relevant bindings. I'd definitely prefer to put all of the relevant local bindings in scope for _every_ HsVar, but that seemed less amenable to being merged :)<o:p></o:p></p>
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<o:p> </o:p></p>
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On Wed, Aug 28, 2019 at 4:56 AM Simon Peyton Jones <<a href="mailto:simonpj@microsoft.com">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;margin-left:36.0pt">
how receptive would y'all be to a patch that puts the `TcLclEnv`, or something similar inside `XUnboundVar GhcTc`.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">That sounds plausible. But is an unbound-var the only place an editor/IDE tooling might want to get its hands on such a thing? ie would that solve your problem, but not the
next person’s?<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Also note that you could easily build up a list of all the in-scope Ids simply by gathering them from the tree as you walk inwards. There’s no actual need for a new function --
although I can see it might be more convenient.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Simon<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> ghc-devs <<a href="mailto:ghc-devs-bounces@haskell.org" target="_blank">ghc-devs-bounces@haskell.org</a>>
<b>On Behalf Of </b>Sandy Maguire<br>
<b>Sent:</b> 18 August 2019 01:28<br>
<b>To:</b> <a href="mailto:ghc-devs@haskell.org" target="_blank">ghc-devs@haskell.org</a><br>
<b>Subject:</b> Getting a hole's relevant local binds?</span><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:6.0pt">Hi all,<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:6.0pt">I'm trying to get my hands on the relevant local binds (as reported by ghc in the presence of a type hole) for editor tooling support. Tracing the code suggests that these things come
from the `TcLclEnv`, but afaict, all remnants of `TcLclEnv` are thrown away by the time we get a `TypecheckedModule`.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:6.0pt"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:6.0pt">Am I mistaken in this? If not, how receptive would y'all be to a patch that puts the `TcLclEnv`, or something similar inside `XUnboundVar GhcTc`. This way editors would have an easy means
of getting their hand on whatever is in scope at the site of a hole, without resorting to parsing error messages.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:6.0pt"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:6.0pt">Cheers,<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:6.0pt">Sandy<br clear="all">
<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:6.0pt"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:6.0pt">-- <o:p>
</o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:6.0pt">I'm currently traveling the world, sleeping on people's couches and doing full-time collaboration on Haskell projects. If this seems interesting to you, please consider signing up as a
host! <a href="https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fisovector.github.io%2Ferdos%2F&data=02%7C01%7Csimonpj%40microsoft.com%7Cd7c51847a19c4d6aa84208d72c42e32b%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637026538110642901&sdata=UClCONCXwkap3HhQ5hZroULJ67uy08UsndYgsrIcvxg%3D&reserved=0" target="_blank">https://isovector.github.io/erdos/</a><o:p></o:p></p>
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<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal">I'm currently traveling the world, sleeping on people's couches and doing full-time collaboration on Haskell projects. If this seems interesting to you, please consider signing up as a host! <a href="https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fisovector.github.io%2Ferdos%2F&data=02%7C01%7Csimonpj%40microsoft.com%7Cd7c51847a19c4d6aa84208d72c42e32b%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637026538110652887&sdata=koBEz03JagWpN7NeS9qbBWqpUK5psZoGoz7fwQxgGp8%3D&reserved=0" target="_blank">https://isovector.github.io/erdos/</a><o:p></o:p></p>
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