Re: [RFC] [PATCH 0/5] Implement 'prior' commit object links (and

Junio C Hamano wrote:

quoted

* "prior" - heads that represent topic branch merges
   

This is not any different from usual "parent" at all (but you
have to think about it a bit to realize it).
[...]
Once you start reading the commit parent to mean " considering
what all of these commits have, what this new commit has suits
my purpose better", it becomes clear that the "previous" pointer
for a branch like my "pu" is just another "parent".
 

How can you look back at the merge history and determine which of these
scenarios is the case?

It still looks like to me that you are recording two distinct types of
parent using the same type of link.  You're now just expanding the
definition of parent so they look to be the same.

Actually it might be alright if you have an extra merge commit object. 
ie, make a complete merge of the new tips, then make a second merge that
merges the two heads.  It's still a little bit of a research topic to
look at that mess and figure out which type of relationship each parent
actually is, but if you really want to decide that is that and done is
done then I guess we'll all just have to live with it or fork.

Sam.