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<p class="MsoNormal" style="margin-left:36.0pt">Solution is to change directory (cd) somewhere else and try again. (There's also cabal install -z flag feature request, -z to ignore local project; but it's not yet merged).<o:p></o:p></p>
<p class="MsoNormal">Yes, that’s what I worked out in the end. But it doesn’t feel like a solution; it feels like a workaround.<o:p></o:p></p>
<p class="MsoNormal">My point is that (for this user at least) it’s deeply strange. I would not expect ‘apt install <blah>’ to behave differently in different directories. I’m saying “please do X” – in this case install a package – and it’s terribly confusing
to me if that’s radically affected by which directory I’m in.<o:p></o:p></p>
<p class="MsoNormal">I’m not saying it’s wrong – everything about UI is a judgement – just that it may be very counter-productive for some users.<o:p></o:p></p>
<p class="MsoNormal">Simon<span style="color:windowtext"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:windowtext"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin:0cm;margin-bottom:.0001pt"><b><span lang="EN-US" style="color:windowtext;mso-fareast-language:EN-GB">From:</span></b><span lang="EN-US" style="color:windowtext;mso-fareast-language:EN-GB"> Oleg Grenrus <oleg.grenrus@iki.fi>
<br>
<b>Sent:</b> 31 May 2019 09:31<br>
<b>To:</b> Simon Peyton Jones <simonpj@microsoft.com>; cabal-devel@haskell.org<br>
<b>Subject:</b> Re: Cabal install<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p>Hi Simon,<o:p></o:p></p>
<p>I see, you triggered another feature/bug of cabal install, namely when you are in a project directory, project settings affect solving process. And when there's a .cabal file, it's a project.<br>
So cabal tried to find an install plan containing local packages (that makes sense, if you try to install local lhs2tex for example!)<br>
<br>
Solution is to change directory (cd) somewhere else and try again. (There's also cabal install -z flag feature request, -z to ignore local project; but it's not yet merged).<o:p></o:p></p>
<p>- Oleg<o:p></o:p></p>
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<p class="MsoNormal">On 31.5.2019 11.02, Simon Peyton Jones wrote:<o:p></o:p></p>
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<p class="MsoNormal">Thanks Oleg<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt">my first guess is that: when working on the unsaturated type families paper, you did `cabal install --lib report`; or something similar. `report` is probably some internal library to that paper / project.<o:p></o:p></p>
<p class="MsoNormal">I am confident I did nothing like that. But there is a file called report.cabal in the directory where I did the ‘cabal install lhs2tex’ command.<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt">To confirm, check what is in your ~/.ghc/x86_64-linux-8.6.5/environments/default (or similar), is some `package-id report-0.1.0.0-hexhash` line there?<o:p></o:p></p>
<p class="MsoNormal">There is no such file:<o:p></o:p></p>
<p class="Code">bash$ ls ~/.ghc<o:p></o:p></p>
<p class="Code">ghci_history x86_64-linux-8.9.0.20190414 x86_64-linux-8.9.0.20190508<o:p></o:p></p>
<p class="Code">x86_64-linux-8.6.4 x86_64-linux-8.9.0.20190430 x86_64-linux-8.9.0.20190527<o:p></o:p></p>
<p class="Code">bash$ ls ~/.ghc/x86_64-linux-8.6.4/<o:p></o:p></p>
<p class="Code">package.conf.d<o:p></o:p></p>
<p class="MsoNormal"><span style="color:windowtext">Simon</span><o:p></o:p></p>
<p class="MsoNormal"><span style="color:windowtext"> </span><o:p></o:p></p>
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<p class="MsoNormal" style="margin:0cm;margin-bottom:.0001pt"><b><span lang="EN-US" style="color:windowtext;mso-fareast-language:EN-GB">From:</span></b><span lang="EN-US" style="color:windowtext;mso-fareast-language:EN-GB"> Oleg Grenrus
<a href="mailto:oleg.grenrus@iki.fi"><oleg.grenrus@iki.fi></a> <br>
<b>Sent:</b> 30 May 2019 20:19<br>
<b>To:</b> Simon Peyton Jones <a href="mailto:simonpj@microsoft.com"><simonpj@microsoft.com></a>;
<a href="mailto:cabal-devel@haskell.org">cabal-devel@haskell.org</a><br>
<b>Subject:</b> Re: Cabal install</span><o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
<p>Hi Simon,<br>
<br>
my first guess is that: when working on the unsaturated type families paper, you did `cabal install --lib report`; or something similar. `report` is probably some internal library to that paper / project.<br>
<br>
In that case, you are hitting the unfortunate cabal bug [1].<br>
<br>
To confirm, check what is in your ~/.ghc/x86_64-linux-8.6.5/environments/default (or similar), is some `package-id report-0.1.0.0-hexhash` line there? If so, the simplest fix is to remove that environment file.<br>
<br>
- [1] <a href="https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fhaskell%2Fcabal%2Fissues%2F5888&data=02%7C01%7Csimonpj%40microsoft.com%7C287418e6b3e247b9b0ec08d6e5a258c4%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636948882792816120&sdata=Xo9%2FS%2BkTGwMtCCOxh023gBA95fhWjQDJPJ884u%2BakFY%3D&reserved=0">
https://github.com/haskell/cabal/issues/5888 </a><a href="https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fhaskell%2Fcabal%2Fissues%2F5559&data=02%7C01%7Csimonpj%40microsoft.com%7C287418e6b3e247b9b0ec08d6e5a258c4%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636948882792826128&sdata=oMPeTq2zVN0cGAGmFUT9BMUK%2FVPSmOvNDnum4VUSv7o%3D&reserved=0">https://github.com/haskell/cabal/issues/5559<span style="color:blue"><br>
</span></a><o:p></o:p></p>
<p>Cheers,<br>
Oleg<o:p></o:p></p>
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<p class="MsoNormal">On 30.5.2019 16.50, Simon Peyton Jones wrote:<o:p></o:p></p>
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<p class="MsoNormal">Dear friendly Cabal folk<o:p></o:p></p>
<p class="MsoNormal">Here’s what happened to me today<o:p></o:p></p>
<p class="Code">bash$ cabal install lhs2tex<o:p></o:p></p>
<p class="Code">cabal: Could not resolve dependencies:<o:p></o:p></p>
<p class="Code">[__0] next goal: report (user goal)<o:p></o:p></p>
<p class="Code">[__0] rejecting: report-0.1.0.0 (conflict: requires UnsaturatedTypeFamilies)<o:p></o:p></p>
<p class="Code">[__0] fail (backjumping, conflict set: report)<o:p></o:p></p>
<p class="Code">After searching the rest of the dependency tree exhaustively, these were the<o:p></o:p></p>
<p class="Code">goals I've had most trouble fulfilling: report<o:p></o:p></p>
<p class="MsoNormal">Crumbs. What is ‘report’? Why does it need UnsaturatedTypeFamilies? I’m totally lost.<o:p></o:p></p>
<p class="MsoNormal">Then, in an inspired moment, I thought to change to a different directory, ~/tmp.
<o:p></o:p></p>
<p class="MsoNormal">Then quite different things happened – it downloaded and built relevant libraries.<o:p></o:p></p>
<p class="MsoNormal">I think that there just happened to be a .cabal file in the original directory I was in at the time. That appears to affect what ‘cabal install’ does in a truly radical way.<o:p></o:p></p>
<p class="MsoNormal">My point is this: this is terribly confusing for the user (at least for this on). I’d be shocked if ‘apt install blah’ behaved utterly differently in different directories. I’m going to make a little empty directory somewhere, and cd
to it before invoking cabal in future. But that just feels like a workaround, not a solution.<o:p></o:p></p>
<p class="MsoNormal">I’m not saying it’s wrong – just giving you a data point that it had one user completely stumped<o:p></o:p></p>
<p class="MsoNormal">Simon<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="Code"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span><o:p></o:p></p>
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<br>
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</span><o:p></o:p></p>
<pre>_______________________________________________<o:p></o:p></pre>
<pre>cabal-devel mailing list<o:p></o:p></pre>
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