I think that butterfly effect piece pretty much exactly described my problems with trying to install yesod and warp. <br>Installing one would uninstall the other. <br>
<br><br><div class="gmail_quote">On Thu, Mar 24, 2011 at 12:56 PM, Thomas Hartman <span dir="ltr"><<a href="mailto:thomashartman1@googlemail.com">thomashartman1@googlemail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
I'm not sure but my guess is these problems are caused by underlying<br>
problem in cabal. See<br>
<br>
<a href="http://cdsmith.wordpress.com/2011/01/21/a-recap-about-cabal-and-haskell-libraries/" target="_blank">http://cdsmith.wordpress.com/2011/01/21/a-recap-about-cabal-and-haskell-libraries/</a><br>
<a href="http://cdsmith.wordpress.com/2011/01/17/the-butterfly-effect-in-cabal/" target="_blank">http://cdsmith.wordpress.com/2011/01/17/the-butterfly-effect-in-cabal/</a><br>
<div><div></div><div class="h5"><br>
On Thu, Mar 24, 2011 at 9:50 AM, Rick Richardson<br>
<<a href="mailto:rick.richardson@gmail.com">rick.richardson@gmail.com</a>> wrote:<br>
> Thanks. So what exactly is the real issue? Is something requiring multiple<br>
> versions of Network as indicated above, or is it a more 'permanent' problem?<br>
><br>
><br>
> On Thu, Mar 24, 2011 at 2:54 AM, Michael Snoyman <<a href="mailto:michael@snoyman.com">michael@snoyman.com</a>><br>
> wrote:<br>
>><br>
>> What Blake suggests in the right solution, except for two points<br>
>> (which are beyond his control):<br>
>><br>
>> * It's a bit unfair to make users remember to install yesod with<br>
>> -fproduction.<br>
>> * wai-handler-devel does not handle Hamlet dependency tracking. That<br>
>> means that if you use Blake's suggestion and then modify your Hamlet<br>
>> templates, your code will not be reloaded.<br>
>><br>
>> So I've released new versions of wai-handler-devel (0.2.1) and yesod<br>
>> (0.7.2). There's no such thing as the -fproduction flag to yesod: it<br>
>> will never build against wai-handler-devel. When you call the<br>
>> develServer function, it will simply print out a message apologizing<br>
>> that it cannot fulfill your request, and will tell you to install<br>
>> wai-handler-devel >= 0.2.1 and run a command such as:<br>
>><br>
>> wai-handler-devel 3000 Controller withTest --yesod<br>
>><br>
>> Notice that extra --yesod at the end? That's the new feature in 0.2.1.<br>
>> I moved the Hamlet dependency checking code from yesod to<br>
>> wai-handler-devel. So now, if you run your application this way,<br>
>> Hamlet changes will automatically result in a reload of your code.<br>
>><br>
>> I tried to set up the develServer function to automatically run<br>
>> wai-handler-server, but it resulted in the same error messages from<br>
>> GHC. Oh well. I image in future versions of the scaffolding tool, the<br>
>> devel-server.hs function will do all this for you automatically.<br>
>><br>
>> Please let me know if this new approach causes any issues.<br>
>><br>
>> Michael<br>
>><br>
>> On Thu, Mar 24, 2011 at 1:00 AM, Blake Rain <<a href="mailto:blake.rain@gmail.com">blake.rain@gmail.com</a>> wrote:<br>
>> > I too had a the same problem with duplicate symbols from libHSghc, and<br>
>> > it seems to be a problem with yesod's dynamic server (or perhaps with<br>
>> > Hint).<br>
>> ><br>
>> > My solution was first to remove the dependency on wai-handler-devel in<br>
>> > the yesod package by using the 'production' flag, like so:<br>
>> ><br>
>> > $ cabal install yesod -fproduction<br>
>> ><br>
>> > For running a dynamic server, the wai-handler-devel package installs an<br>
>> > executable called wai-handler-devel. You can use this rather than the<br>
>> > "runhaskell devel-server.hs" by providing the port, module and function<br>
>> > from your "devel-server.hs" file as arguments:<br>
>> ><br>
>> > $ wai-handler-devel 3000 MySiteModule withMySite<br>
>> ><br>
>> > The dynamic recompilation of wai-handler-devel is very useful, and I<br>
>> > hope this helps.<br>
>> ><br>
>> > On Wed, 2011-03-23 at 14:22 -0400, Rick Richardson wrote:<br>
>> >> I removed all but network-2.2.1.0 and rebuilt everything, still no<br>
>> >> luck. But I'm sure you have set me on the right track, I will<br>
>> >> experiment with other permutations.<br>
>> >><br>
>> >><br>
>> >> Thanks.<br>
>> >><br>
>> >><br>
>> >><br>
>> >><br>
>> >> On Wed, Mar 23, 2011 at 1:27 PM, Anton Cheshkov <<a href="mailto:acheshkov@gmail.com">acheshkov@gmail.com</a>><br>
>> >> wrote:<br>
>> >> Hi Rick! I got the the same error day ago on my server.<br>
>> >> Probably it happens because you have two network packages in<br>
>> >> you system.<br>
>> >><br>
>> >> Try to compile all your packages only on network-2.2.1.10,<br>
>> >> and delete package network-2.3<br>
>> >><br>
>> >><br>
>> >> Hope it helps you<br>
>> >><br>
>> >><br>
>> >> 2011/3/23 Rick Richardson <<a href="mailto:rick.richardson@gmail.com">rick.richardson@gmail.com</a>><br>
>> >><br>
>> >><br>
>> >><br>
>> >> I just installed the generic 7.0.2 binary on Ubuntu<br>
>> >> on both 32 bit and 64 bit machines. Then I rm'd<br>
>> >> .ghc and .cabal then fetched the current haskell<br>
>> >> platform. Built and installed.<br>
>> >><br>
>> >><br>
>> >> After cabal installing all of the dependencies cabal<br>
>> >> said were required for yesod, I run yesod.. the<br>
>> >> script creates the project.<br>
>> >><br>
>> >><br>
>> >> When executing runhaskell devel-server.hs I get this<br>
>> >> message<br>
>> >><br>
>> >><br>
>> >> GHCi runtime linker: fatal error: I found a duplicate<br>
>> >> definition for symbol<br>
>> >> ghczm7zi0zi2_AsmCodeGen_zdfMonadCmmOptM2_closure<br>
>> >> whilst processing object file<br>
>> >><br>
>> >> /usr/local/lib/ghc-7.0.2/ghc-7.0.2/libHSghc-7.0.2.a<br>
>> >> This could be caused by:<br>
>> >> * Loading two different object files which export<br>
>> >> the same symbol<br>
>> >> * Specifying the same object file twice on the GHCi<br>
>> >> command line<br>
>> >> * An incorrect `package.conf' entry, causing some<br>
>> >> object to be<br>
>> >> loaded twice.<br>
>> >> GHCi cannot safely continue in this situation.<br>
>> >> Exiting now. Sorry.<br>
>> >><br>
>> >><br>
>> >><br>
>> >><br>
>> >> it's the same on both 32 and 64 bit.<br>
>> >><br>
>> >><br>
>> >> Any ideas? I am going to try to build 7.0.2 from<br>
>> >> source to see if that fixes it.<br>
>> >><br>
>> >><br>
>> >> _______________________________________________<br>
>> >> web-devel mailing list<br>
>> >> <a href="mailto:web-devel@haskell.org">web-devel@haskell.org</a><br>
>> >> <a href="http://www.haskell.org/mailman/listinfo/web-devel" target="_blank">http://www.haskell.org/mailman/listinfo/web-devel</a><br>
>> >><br>
>> >><br>
>> >><br>
>> >><br>
>> >> --<br>
>> >> Best regards,<br>
>> >> Cheshkov Anton<br>
>> >> Phone: <a href="tel:%2B7%20909%20005%2018%2082">+7 909 005 18 82</a><br>
>> >> Skype: cheshkov_anton<br>
>> >><br>
>> >><br>
>> >><br>
>> >> _______________________________________________<br>
>> >> web-devel mailing list<br>
>> >> <a href="mailto:web-devel@haskell.org">web-devel@haskell.org</a><br>
>> >> <a href="http://www.haskell.org/mailman/listinfo/web-devel" target="_blank">http://www.haskell.org/mailman/listinfo/web-devel</a><br>
>> ><br>
>> ><br>
>> ><br>
>> > _______________________________________________<br>
>> > web-devel mailing list<br>
>> > <a href="mailto:web-devel@haskell.org">web-devel@haskell.org</a><br>
>> > <a href="http://www.haskell.org/mailman/listinfo/web-devel" target="_blank">http://www.haskell.org/mailman/listinfo/web-devel</a><br>
>> ><br>
><br>
><br>
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><br>
><br>
</div></div></blockquote></div><br>