Thanks Paul. You may be right, but our aim is to offload versioning onto a VCS and the version number has primacy: we want to assemble the filename in part from it, not extract the version number from the filename.

As background: the VCS goal is important to us. It costs us dearly whenever people squirrel away a document, edit it as a personal copy and email it around: by the time it re-enters the pool of collaborators it's wildly out of sync with other edits, often its filename has changed and no longer matches its cover-page title, its Version property hasn't been updated, and untraceable copies remain scattered from hell to breakfast.

It's a sloppy approach which I know we documenters tolerate, with the increasingly weak excuse that VCS isn't as flexible with binary documents as it is with text. I also know that programmers who defy a VCS regime are howled by their peers into toeing the line.