Re: [VM] The "Google docs" paradigm

[Uday Reddy]

Kurt Hackenberg writes:

> VM followed that model -- no concurrent visiting of a given folder --
> and should continue to, IMHO, for local folders.  (Or apparently
> local, like NFS.)  Partly because VM works by editing the whole mbox
> file, and would have to be redesigned to work any other way.
> 
> But you're talking about VM being an IMAP client, aren't you?  And
> assuming that other clients on other computers are modifying the IMAP
> folder concurrently.

Indeed, I am talking about IMAP folders.  For local folders, there is no
possibility of concurrent usage (not unless file systems start understanding
email).  The No. 1 reason for switching to IMAP is to get concurrent access.
The IMAP server is in a sense a "file system that understands email".

> I don't have much opinion, but sort of like the idea of things
> happening immediately.  IMAP can do that, and sort of looks like it's
> meant to.  How do other IMAP clients do it?

It would be possible to add a timer task that wakes up every N seconds and
synchronizes the VM folder with the IMAP server.  That is how, I think,
Thunderbird and perhaps other clients do it.  They don't have a "SAVE"
button.

To be consistent, we also need to update the cache folder on disk when we
update the IMAP server.

The main problem with providing such a function is that it is at odds with
the Emacs philosophy.  Long-time Emacs users are used to the idea that they
can make changes to buffers inside Emacs and discard the changes if things
go wrong.  In VM, I often end up expunging a folder and then realizing that
I shouldn't have.  Then I can reload the folder and return to the version on
the disk or the server.  If the changes get saved asynchronously without my
control, I would lose that ability to discard.

> I think it's acceptable for VM to have that difference in timing
> between IMAP folders and local folders.  VM users are knowledgeable
> enough not to be confused by that.  (Emacs is a programmer's editor,
> and VM strikes me as a programmer's mail reader.  I expect that
> everybody who uses either program is technically knowledgeable.  The
> general public doesn't know that Emacs and VM exist, much less use
> them, and never will.)

Yup.  I think I agree.  

Cheers,
Uday