base library and GHC 6.12

[Ross Paterson]

On Thu, Jun 25, 2009 at 04:02:14PM +0100, Ian Lynagh wrote:
> Option 1
> --------
> 
> In order to solve the version number issue, we could simply state that
> "base follows the PvP, but only for shared module hierarchies". However,
> it would be impossible for packages which /do/ need GHC.* modules to
> give accurately versioned dependencies, and it wouldn't solve the other
> issue at all.

There's an existing policy of no change to the portable modules or
GHC.Exts in GHC bugfix releases, and it seems it is the practice to
increase the first component of base's version with each major GHC
release.  Perhaps formalizing that (which is consistent with the PVP)
would be enough:

- packages that use only the public API depend on base < 5
- packages that use the GHC internal modules depend on base < 4.x

It does mean that packages need to be updated each year, if only to
update their dependencies.