graph of port dependencies?

[Rainer Müller]

On 07/27/2011 07:17 PM, Andrew Long wrote:
> Does anyone know of a program that will draw a graph of dependencies
> between ports? Forex, if I select a library that I want to uninstall,
> I want a graph of all 'top-level' ports that depend on it, so I can
> make an early decision about keeping it or not, rather than just
> trying to uninstall it and finding out that it is a dependency for a
> port that I wnt to keep?

Isn't the output of
   port rdependents libfoo
enough to see why a specific port has been installed?

I understand that this can be long and you just want a single port name, 
so maybe try something like this:

   port echo rdependentof:libfoo and requested
or:
   port echo rdependentof:libfoo and leaves

rdependentof: recursively finds all ports in the dependents, requested 
restrict to the ports which have explicitely been listed as an argument 
to install, leaves restricts it to the requested ports without dependents.

For drawing graphs, there is the port-rdeps script which dates back 
before we had 'port rdeps' in MacPorts.

   http://trac.macports.org/browser/contrib/port-rdeps/port-rdeps

Rainer