PVP proposal: no upper bounds on non-upgradeable packages

[Michael Snoyman]

At Herbert's request, I'm splitting off this part of the PVP proposal I
made[1] to its own separate proposal. Same discussion period of three
weeks. The proposal is:

Upper bounds should not be included on non-upgradeable packages, such as
base and template-haskell (are there others?). Alternatively, we should
establish some accepted upper bound on these packages, e.g. many people
place base < 5 on their code.

The purpose (elaborated in my blog post[2]) is that these upper bounds
virtually never provide for a successful build. Instead, they are purely
about what error messages the user receives. With this change:

* Some build plans that would have previously been impossible are now
possible, without resorting to the nuclear option of --allow-newers.
* Instead of cabal version bound error messages, users get GHC compiler
errors that can be fed back upstream to help get packages fixed more
expediently.

Downsides I'm aware of:

* If you consider the cabal error messages more user friendly, then the
error message quality goes down.
* Users may find out later than they do right now about a failing build.

[1] http://www.haskell.org/pipermail/libraries/2014-April/022529.html
[2] http://www.yesodweb.com/blog/2014/04/proposal-changes-pvp
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/libraries/attachments/20140409/90237509/attachment.html>