Re: Finer Extension dependencies

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>
To: Peter Eisentraut <peter_e@gmx.net>
Cc: Hitoshi Harada <umi.tanuki@gmail.com>, Dimitri Fontaine <dimitri@2ndquadrant.fr>, Alvaro Herrera <alvherre@commandprompt.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2012-03-29T18:39:04Z
Lists: pgsql-hackers
On Thu, Mar 29, 2012 at 2:28 PM, Peter Eisentraut <peter_e@gmx.net> wrote:
> On ons, 2012-03-28 at 23:00 -0700, Hitoshi Harada wrote:
>> I totally agree with Robert's point that one feature is not
>> standardized and nobody can tell how you can depend on the feature in
>> the end.  Mind you, I've never heard about building dependency by its
>> name as a string in other packaging system.  If you want to introduce
>> the concept of version dependency not feature name dependency, do
>> *it*;  I don't think feature dependency solves it.
>
> The Python setuptools (a.k.a. distutils a.k.a. distribute a.k.a. eggs
> a.k.a. easy_install a.k.a. dont-get-me-started) system supports feature
> names that a package can provide, but it uses them for a different
> purpose.  The idea is that a package "foo" can depend on a package
> "bar[somethingextra]", and then bar itself would declare it's
> dependencies such that it depends, say, on "ham", but if feature
> "somethingextra" is required, it also depends on "eggs".
>
> This is actually quite useful,

Wow.  That is complex, but I agree that it's useful.

> but it breaks down when you, say, want to
> wrap your egg into a Debian package.

*blink* Huh?

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company