extracting base names from package listing

[Andrew Gould]

pkg_info provides a nice listing of package names that
include version numbers.  I'd like to have a list of
the names without the version numbers so that I can
write a script to install the newer versions after a
clean installation.

Looking at the package names, I'm having a hard time
coming up with an algorithm for separating the package
names from the version numbers.  Many package names
have dashes (postgresql-server), and some have letters
in the version numbers (libid3tag-0.15.1b).

Does anyone have a good way of separating the package
names from the version numbers?

Is there a better way of identifying and installing a
set of packages after a clean installation?

Any help would be appreciated.

Thanks,

Andrew L. Gould