On Tue, Nov 9, 2010 at 5:12 PM, Duncan Coutts <span dir="ltr"><<a href="mailto:duncan.coutts@googlemail.com">duncan.coutts@googlemail.com</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="im">On 9 November 2010 10:40, John Lato <<a href="mailto:jwlato@gmail.com">jwlato@gmail.com</a>> wrote:<br>
>> On the other hand, on those systems people would get all packages<br>
>> (libraries and programs) required by the Haskell platform, plus<br>
>> some additional ones. Wouldn't hurt too much, IMHO (allthough it<br>
>> feels a little bit wrong if the platform would contain programs<br>
>> that can't be built with only the platform).<br>
><br>
> I think this was exactly the situation rationale 8.5 means to avoid.<br>
> I do think it would be technically possible to make this work, but only by<br>
> greatly increasing the maintenance cost for HP (I underestimated this cost<br>
> originally). It's probably not a good trade-off.<br>
<br>
<br>
> If cabal supported something like run-time-specified repos it would be much simpler.<br>
<br>
</div>What sort of thing are you thinking of here?</blockquote><div><br></div><div>If, in addition to the global and user package stores, you could specify alternate package stores. Then it would be possible to do e.g.</div>
<div><br></div><div>cabal install --use-package-store=./buildlibs</div><div><br></div><div>to create a package store at ./buildlibs (if it doesn't exist) and install a library there. Then later commands could do</div>
<div><br></div><div>cabal install --extra-package-store=./buildlibs</div><div><br></div><div>to check for packages in that extra location in addition to the default global and user locations.</div><div><br></div><div>This would certainly enable building non-blessed libs as part of the HP and differentiating from the normal blessed packages. It might be useful for other reasons too. I'm not saying it's a good idea for HP, just that it would be technically possible.</div>
<div><br></div><div>Were some other people already talking about this in this thread? Is this already implemented? </div><div><br></div><div>John</div></div>