The PVP ought to mention dependency bounds (Was: Growing Haskell Platform)

Ian Lynagh ian at
Fri Dec 7 17:41:54 CET 2012

On Fri, Dec 07, 2012 at 08:30:45AM -0800, Johan Tibell wrote:
> On Fri, Dec 7, 2012 at 8:28 AM, Ian Lynagh <ian at> wrote:
> > On Fri, Dec 07, 2012 at 08:20:41AM -0800, Johan Tibell wrote:
> >>
> >> If B only bumps its patch-level version (i.e. to B-, C no
> >> longer compiles (due to a version constraint failure) with B-
> >
> > Won't cabal-install select B-1.0 in that case, so installing C will
> > still work?
> See my aside at the end. Yes, it will backtrack and use the older
> version, but the users might get confused why the new version isn't
> used as it's version number suggests that it could be.

I don't think most users would notice, and for those that do the "-v"
flag to cabal-install ought to tell them why.

I don't think this (theoretical?) confusion issue is worth the effort of
bumping major versions all the way up the dependency tree.


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