Haskell Platform universe

[Bulat Ziganshin]

it seems that i should forward here my letter from Haskell Platform
list:

i just installed Windows Haskell Platform RC. it have created
"Start Menu\Haskell Platform\GHC 6.10.2" item, that forced me to think
deeper about HP universe

yes, we decided that HP will include up-to-date GHC and some set of
libraries. but how different HP versions will coexist?

one model is that every HP is separate universe, with its own GHC and
libs carried - this case menu item (and disk directory) should be
called something like "Start Menu\Haskell Platform\2009.0.0"

another model is that each HP release updates HP universe already existing on
user's box. i.e. it comes with some versions of GHC and libs while this
universe may already contain this and previous GHC versions and some
libraries so HP should be carefully installed in order to not lose old
contents (such as ghc-pkg database)

i fear that currently this topic was not considered and we don't
support any model at all. i.e. every next HP release will just
overwrite universe with fresh GHC installation making it suitable only
for beginners

well, the good news is that we can make a *first* release that does
clean installation and add "update" feature only staring from the
second one (well, as far as users will not install first release attop of
later ones :)


-- 
Best regards,
 Bulat                            mailto:Bulat.Ziganshin at gmail.com