<div dir="ltr">On Tuesday, September 13, 2016 at 10:05:44 PM UTC+2, Christopher Allen wrote:<blockquote class="gmail_quote" style="margin: 0;margin-left: 0.8ex;border-left: 1px #ccc solid;padding-left: 1ex;">Stack users are moving away from enabling system installed GHCs by<br>default because it breaks the ease of enabling profiling for libraries<br>when you're using a Stack-installed GHC.</blockquote><div> </div><blockquote class="gmail_quote" style="margin: 0;margin-left: 0.8ex;border-left: 1px #ccc solid;padding-left: 1ex;"><p>I'm not sure why multiple system-installed GHCs needs to be supported<br>in addition to the GHC support Stack already provides. That's extra<br>work for...what? Stack isn't trying to compete with Nix. It's more<br>like a blend of rustup and cargo -- or Clojure's Leiningen.</p></blockquote><div><br>To clarify: I'm not proposing stack to install those GHCs, just to use them.<br><br>I think the extra work would be limited (calling GHC-X.Y.Z instead of GHC) and has other technical advantages (https://github.com/commercialhaskell/stack/issues/2433). Mind you, I'm willing to contribute the work and not asking anybody—I've just been busy.<br><br>Right now I have to modify the PATH every time I use GHC 7.8.4 because I needed to customize the build (I'm on OS X 10.11), but I still want GHC 8 by default.</div><div> </div><blockquote class="gmail_quote" style="margin: 0;margin-left: 0.8ex;border-left: 1px #ccc solid;padding-left: 1ex;"><p>On Tue, Sep 13, 2016 at 3:01 PM, Paolo Giarrusso <<a href="javascript:" target="_blank" gdf-obfuscated-mailto="M_qSMCr2AgAJ" rel="nofollow" onmousedown="this.href='javascript:';return true;" onclick="this.href='javascript:';return true;">p.gia...@gmail.com</a>> wrote:<br>><br>><br>> On Tuesday, September 13, 2016 at 9:47:20 PM UTC+2, Richard Eisenberg wrote:<br>>><br>>> Thanks, many, for explaining better ways to interact directly with GHC<br>>> after using a `stack setup`. Perhaps, then, all that’s stopping someone like<br>>> me from liking the ease of `stack setup` is a little missing PR (as in,<br>>> public relations). I understand that many people want to keep GHC cloistered<br>>> away to ease version swapping, but others (like me) want GHC available front<br>>> and center.<br>>><br>>> Other minor points:<br>>> `stack env` does not work for me: my version of stack does not know how to<br>>> `env`.<br>><br>><br>> That's correct—stack env was a feature request.<br>><br>> The warning on `stack ghci` doesn't happen usually, but I'd say that's a bug<br>> (probably because it's a new install)?<br>><br>> I use stack (and have contributed a bit recently), but I agree there's a few<br>> things stack could do better for this workflow.<br>><br>> And the transition has a rather annoying learning curve—stack ghci and stack<br>> ghc are not the same as ghci/ghc. I think that's on purpose to support a<br>> project-based workflow, and it has upsides, but it's a transition pitfall.<br>>  Lots of things *are* explained in<br>> <a href="https://docs.haskellstack.org/en/latest/faq/" target="_blank" rel="nofollow" onmousedown="this.href='https://www.google.com/url?q\x3dhttps%3A%2F%2Fdocs.haskellstack.org%2Fen%2Flatest%2Ffaq%2F\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNFOQsXj2vn9xd87qv5H1CS8LUEZYw';return true;" onclick="this.href='https://www.google.com/url?q\x3dhttps%3A%2F%2Fdocs.haskellstack.org%2Fen%2Flatest%2Ffaq%2F\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNFOQsXj2vn9xd87qv5H1CS8LUEZYw';return true;">https://docs.haskellstack.org/<wbr>en/latest/faq/</a>, but you do need learn a few<br>> things from scratch.<br>><br>> You want stack exec ghc and stack exec ghci, and arbitrary options require a<br>> double dash `--` — use `stack ghc -- --version` or `stack exec -- ghc<br>> --version`. And I'm afraid the command syntax is mostly frozen by now.<br>><br>> To support a compiler-based workflow, there are a few things planned—I<br>> opened an issue to collect them, starting from Simon Marlow's recent email:<br>> <a href="https://github.com/commercialhaskell/stack/issues/2546" target="_blank" rel="nofollow" onmousedown="this.href='https://www.google.com/url?q\x3dhttps%3A%2F%2Fgithub.com%2Fcommercialhaskell%2Fstack%2Fissues%2F2546\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNGsJi8ewoYU1JsKuTR7ThuhsV2q6g';return true;" onclick="this.href='https://www.google.com/url?q\x3dhttps%3A%2F%2Fgithub.com%2Fcommercialhaskell%2Fstack%2Fissues%2F2546\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNGsJi8ewoYU1JsKuTR7ThuhsV2q6g';return true;">https://github.com/<wbr>commercialhaskell/stack/<wbr>issues/2546</a><br>><br>> BTW, a system-installed GHC already works if you stick to one (and only<br>> build projects that need that). But I'd love to support multiple<br>> system-installed GHCs and being able to pick the one you need.<br>><br>> As others already explained, giving access to stack-installed GHCs can be<br>> problematic—they're going to work, in part, exactly because you can't<br>> install in their package database.<br>><br>> Having stack install system-wide GHCs would IMHO risk opening a can of<br>> worms—having working binaries for all Linux distros requires some work,<br>> system installers would be harder and most users would dislike them.<br>><br>> ______________________________<wbr>_________________<br>> Haskell-Cafe mailing list<br>> To (un)subscribe, modify options or view archives go to:<br>> <a href="http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe" target="_blank" rel="nofollow" onmousedown="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fmail.haskell.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fhaskell-cafe\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNH7sFgl7KfuDcDlaGGG3ip3kRaoIA';return true;" onclick="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fmail.haskell.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fhaskell-cafe\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNH7sFgl7KfuDcDlaGGG3ip3kRaoIA';return true;">http://mail.haskell.org/cgi-<wbr>bin/mailman/listinfo/haskell-<wbr>cafe</a><br>> Only members subscribed via the mailman list are allowed to post.</p><p></p><p>-- <br>Chris Allen<br>Currently working on <a href="http://haskellbook.com" target="_blank" rel="nofollow" onmousedown="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fhaskellbook.com\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNG46wU2oFQDecd0YpDIDIGbtyVs1Q';return true;" onclick="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fhaskellbook.com\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNG46wU2oFQDecd0YpDIDIGbtyVs1Q';return true;">http://haskellbook.com</a><br>______________________________<wbr>_________________<br>Haskell-Cafe mailing list<br>To (un)subscribe, modify options or view archives go to:<br><a href="http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe" target="_blank" rel="nofollow" onmousedown="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fmail.haskell.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fhaskell-cafe\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNH7sFgl7KfuDcDlaGGG3ip3kRaoIA';return true;" onclick="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fmail.haskell.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fhaskell-cafe\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNH7sFgl7KfuDcDlaGGG3ip3kRaoIA';return true;">http://mail.haskell.org/cgi-<wbr>bin/mailman/listinfo/haskell-<wbr>cafe</a><br>Only members subscribed via the mailman list are allowed to post.</p><p></p><p></p><p></p></blockquote></div>