following-up to my own note: On Oct 8, 2008, at 10:42 AM, zooko wrote:
> See what I mean? That's the key concept of "out-of-band > signalling". Make it so that the metadata which darcs adds and which > darcs parses and hides and uses is completely separate from the patch > comment that the user edits, and make it so the two cannot be > confused with one another. Basically, what I would *really* like is if darcs had a way to put arbitrary key-value pairs into the patch description such that old versions of darcs would ignore key-value pairs whose keys they didn't recognize. Then, we could put "patch-salt" as a key and the salt as a value, it would be completely separate from the patch comment (as it should be), and old versions of darcs would simply ignore it. However, old versions of darcs don't do that. If you put a new field into their patch metadata then they croak with an error. Therefore, the only place where we can stick the patch salt is into the only arbitrary-length field in the darcs metadata, which happens to be the patch comment. However, our goal should be basically to redefine the patch comment so that in the future there are two separate chunks of data in the patch comments: the user-editable, user-visible part which serves the same purpose that the patch comment has always served, and the arbitrary key-value-pairs part which serves as a place where future versions of darcs can exchange new fields with each other without hopelessly confusing darcs 2.1.0 when it sees patches containing those new fields. Make sense? For what it is worth, this is a progression of extensibility and backwards-compatibility and graceful-upgrade that I have observed and participated in several times before. It's a fairly normal process that darcs is going through. :-) Regards, Zooko --- http://allmydata.org -- Tahoe, the Least-Authority Filesystem http://allmydata.com -- back up all your files for $5/month _______________________________________________ darcs-users mailing list [email protected] http://lists.osuosl.org/mailman/listinfo/darcs-users
