Re: [lmi] Autosave

[Vadim Zeitlin]

On Sun, 12 Oct 2014 16:31:21 +0000 Greg Chicares <address@hidden> wrote:

GC> Autosave is a complicated feature, and less is more.

 Sorry, I have to disagree. Avoiding data loss is more, not doing it is less.

GC> How many saved versions are kept? If your answer is...

 The question presupposes that "autosave" means explicitly saving the file
automatically. This is not how this feature is usually implemented however.
Typical implementation never touches the original file(s) without an
explicit user request, however it does continuously preserve the user work
in some other location on disk and allows to restore it from there if the
program finds it there when opening the same file the next time. I can
explain this in more details, of course, but I think you must be already
familiar with this idea.

 This is quite simple and works very well in my experience and is resistant
not only to the bugs in the program itself (which are, at least in theory,
under our control), but also to hardware failures such as power loss (which
could be mitigated by providing an UPS with each LMI copy, but this is
already getting slightly complicated...) and even OS kernel bugs (which,
while rare, still happen and are impossible for us to fix). As an example,
even though I had the total of just 2 crashes in several hundreds of
person-years[*] spent using Vim, I definitely was glad to be able to
restore the latest versions from the swap files when they happened.


GC>  - infinity: I guess that's the One True Answer, which apple is pursuing:
GC>      http://support.apple.com/kb/ht4753

 Putting aside my feelings about Apple, I do think that it's an interesting
idea. However it does much more than autosave: this implements versioning.
It is something very valuable and I do use it all the time (I just use
(local) git repository instead of OS support for this), but goes far beyond
my modest proposal to just avoid losing the user data.

 So I don't advocate doing this, but I still think that keeping the latest
version for the purpose of recovery is a very good idea.

 Regards,
VZ

[*] I started using it only 19 years ago, but considering that I use it 24
    hours a day and usually have half a dozen of instances of Vim opened at
    the same time, I think this might be even an underestimation.