----- Forwarded message from Nathaniel Smith <[email protected]> ----- From: Nathaniel Smith <[email protected]> Date: Fri, 7 Dec 2012 20:45:42 +0000 To: [email protected] Subject: Re: [linux-elitists] Ledger: org mode for double-entry bookkeeping
On Fri, Dec 7, 2012 at 3:17 PM, Don Marti <[email protected]> wrote: > (By the way, I'm now at Perforce, working on related > problems among other things. Although I prefer to use > applications of the future, a lot of people are still > using current mass-market desktop applications that > failed to understand git-merge-friendly principles > when designing their on-disk formats, which is > understandable considering how much longer than git > they've been around.) Last I checked, git's merge algorithm has a lot more heuristics than principled guarantees, which makes the idea of "git-merge-friendly principles" more vacuous than would be ideal. It's sort of a shame, since we actually solved the problem of merging complex structured data in monotone. We used it for merging arbitrary mixes of file/directory renames, but the principles are more general: http://thread.gmane.org/gmane.comp.version-control.monotone.devel/4297 http://thread.gmane.org/gmane.comp.version-control.revctrl/93 http://thread.gmane.org/gmane.comp.version-control.monotone.devel/9781 Unfortunately we only did this *after* git and mercurial's designs "forked off", so the ideas haven't really had any influence. Plain text is actually about the worst case for merging; AFAICT there are still *no* algorithms that don't blow up and do horrible things in some situation or another, because the linear ordering of lines turns out to be a particularly nasty data structure to work with. Merging trees, graphs, email message flags, contact fields, etc. etc. are all totally doable though. If I wanted to be an engineer when I grew up, then I'd convince someone to pay me to write a sort of bastard child of sqlite and git, where you could write a description of complex data structures and it would implement chained-hash-synchronization/delta-compressed-storage/provably-good-merge-algorithms, with a clean API to expose conflicts to the app as structured first-class entities and other niceties useful for synchronizing apps (e.g., pruning history, in case you don't need 15 years of edits to your mail store or calendar). Couchdb kind of wants to be this, but last I checked couchdb doesn't even record merges in its internal history graph, so it's doomed. Unfortunately I decided to be an academic instead, so, no time. -n _______________________________________________ Do not Cc: anyone else on mail sent to this list. The list server is set for maximum one recipient. linux-elitists mailing list [email protected] http://zgp.org/cgi-bin/mailman/listinfo/linux-elitists ----- End forwarded message ----- -- Eugen* Leitl <a href="http://leitl.org";>leitl</a> http://leitl.org ______________________________________________________________ ICBM: 48.07100, 11.36820 http://www.ativel.com http://postbiota.org 8B29F6BE: 099D 78BA 2FD3 B014 B08A 7779 75B0 2443 8B29 F6BE _______________________________________________ fossil-users mailing list [email protected] http://lists.fossil-scm.org:8080/cgi-bin/mailman/listinfo/fossil-users
