libpng transition?

[Dan Ports]

Implicit in here is the assumption that you're always upgrading all of
your outdated ports at once -- `port upgrade outdated`.

If you saw a new version of libpng and decided you wanted to upgrade
it (for all of the exciting new features a graphics library can offer?)
but not all your other ports, `port upgrade libpng` would happily let
you do that and leave most of your system broken. 

I'd be happier if there were a warning that these other ports need to
be upgraded too or they're going to break. Not sure how we could
achieve that, though.

Dan

-- 
Dan R. K. Ports              MIT CSAIL                http://drkp.net/