<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div></div><div><br></div><div><br>On Jun 4, 2015, at 5:41 PM, Brandon Allbery <<a href="mailto:allbery.b@gmail.com">allbery.b@gmail.com</a>> wrote:<br><br></div><blockquote type="cite"><div><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Thu, Jun 4, 2015 at 5:36 PM, Anthony Cowley <span dir="ltr"><<a href="mailto:acowley@seas.upenn.edu" target="_blank">acowley@seas.upenn.edu</a>></span> wrote:<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">
> On Jun 4, 2015, at 5:22 PM, Herbert Valerio Riedel <<a href="mailto:hvr@gnu.org">hvr@gnu.org</a>> wrote:<br>> new syntax, Cabal has no way to know that a new language syntax is<br>
> required and that thereby needs exclude (not implemented yet) the<br>
> affected package versions from the install-plan configuration space.<br><br>
</span>I can't parse your last sentence. The proposed syntax is currently a parse error, so a package that used it could depend on a GHC new enough to support it (eg with a base version constraint). No older packages would cause any errors whatsoever.<br></blockquote><div><br></div><div>Your unstated assumption is that everyone always has the latest ghc.</div><div><br></div><div>How do people who are on, say, Debian or CentOS, deal with a language change that is not compatible with their compiler? How does cabal avoid pulling in package versions using the new incompatible syntax?</div></div><div><br></div></div></div></div></blockquote><div><br></div><div>I guess I'm just not familiar with how Debian and CentOS work, because this doesn't seem like a change to me, but you and hvr have much more experience than I do. How do those systems deal with a package that has a lower bound on base?</div><div><br></div><div>If I require base >= 7.9, does that get thrown out to work with GHC 7.4? How does that work?</div><div><br></div><div>Anthony</div><div><br></div><br><blockquote type="cite"><div><div dir="ltr"><div class="gmail_extra">-- <br><div class="gmail_signature"><div dir="ltr"><div>brandon s allbery kf8nh sine nomine associates</div><div><a href="mailto:allbery.b@gmail.com" target="_blank">allbery.b@gmail.com</a> <a href="mailto:ballbery@sinenomine.net" target="_blank">ballbery@sinenomine.net</a></div><div>unix, openafs, kerberos, infrastructure, xmonad <a href="http://sinenomine.net" target="_blank">http://sinenomine.net</a></div></div></div>
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