topological sorting

[tlaronde%polynum.com@localhost]

Is there already some options:

1) To display the topological sorted graph of the dependencies for a
package one wants to install (one can parse a Makefile for buildlink
inclusions, emitting pairs, recurse and then tsort(1); so the question
is not about a problem of feasability);

2) To verify that there is no version problems about dependencies:
package P is wanted; it depends on packages M and N; M depends on
runtime package O v1; N depends on runtime package O v2; and it is not
possible to have simultaneously Ov1 and Ov2; and same question about
incompatible building dependencies;

3) To instruct to build and install (alternatively to add binary)
in reverse topological order (independant from others to be installed
first).

TIA
-- 
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
                     http://www.kergis.com/
                    http://kertex.kergis.com/
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