Julian Foad wrote on Sun, Sep 25, 2016 at 22:30:54 +0100: > Daniel Shahaf wrote: > >Paul Hammant wrote: > >>[...] It is easiest to > >>hit up the root note and ask for a sha1, [...] > > > >Can you explain more about your use-case? [...] > > Hi Paul. I'm +1 on the concept that implementing content hashes in > Subversion would be useful. I think if we were designing Subversion today, > the question would be "Why on earth wouldn't we design in a Merkle tree > content hash?" as it is obviously (to those who have already thought about > it) useful for these sorts of operation, for people building functionality > on top of Subversion. >
I appreciate that that's your opinion, but I'm going to play devil's advocate and question it. The only operation one can do with a content hash is compare it to another content hash. Our API already has an object with this property: svn_fs_id_t. The equality relation of node-rev id's is a refinement of the equality relation of content hashes: equal node-rev id's imply equal content hashes, but the converse is not true. What would content hashes provide that comparing node-rev id's would not? Cheers, Daniel (Node-rev id's( get changed on every text change, property change, or copy of the node itself, but aren't changed when a parent of the node gets copied.)
