[darcs-users] Revision numbers and unpulling

[Michael G Schwern]

Had a nice little discussion on #darcs tonite about local revision numbers 
and in particular how they work with unpull/undo'ing a patch.  I think this
sums up the idea pretty well.

<beschmi>	afaik (i haven't really looked at the code) they can be reordered when darcs tries to merge a patch http://azure.humbug.org.au/~aj/blog/2004/12/11?seemore=y#2004-12-11-darcs-merging
<Schwern>	beschmi:  When you say reorder... could you explain what that means?
<Schwern>	beschmi:  Does that mean that I have in my local repository changes A, B and C in that order in the change log and D is pulled down that I might wind up with something other than A, B, C and D?
<Schwern>	Like A, B, D and C
<beschmi>	i think so
<Schwern>	Weird.
<Miteorite>	can you not unpull B, and then pull it again and end up with A,C,D,B?
<Schwern>	Miteorite:  That's ok.  It would be (to switch to numbers).  1,2,3,4.  unpull 2.  1,3,4.  pull 2.  1,3,4,5.
<Schwern>	ie. The global "2" becomes your local "5".
<Schwern>	Once you drop the requirement for global identifiers and make them just local identifiers things become easier.
<Miteorite>	ah ha, that works. because they are.. idempotent.
<Schwern>	Oooh, big word. :)
<Schwern>	but exactly right.
<Miteorite>	well as long as we remember that your #2 is my #5 :)
*	Miteorite hugs math.
<Schwern>	Miteorite:  For cross-repository communication you'd continue to use patch names, dates and/or hashes.
<Schwern>	Miteorite:  You don't try to remember that your 2 is my 5.