Re: vc-find-revision-no-save?

[Juri Linkov]

> vc.el contains the following defcustom:
>
>     (defcustom vc-find-revision-no-save nil
>       "If non-nil, `vc-find-revision' doesn't write
> the created buffer to file."
>       :type 'boolean
>       :version "27.1")
>
> Notice that the default is nil.  What is the logic in allowing an
> historic revision to be associated with a file?  Why is it not merely
> a readonly buffer with no backing file?

The default value is nil just to keep its previous default behaviour.
I don't know why previously it saved every visited revision to a file,
thus littering the source directories with useless files.

> Perhaps I have been too influenced by git...  My mental model is that
> revisions are immutable _values_.  Is that not vc's model?

I don't know a reason why anyone might want to edit an old revision.
But anyway when one needs to save a revision to file, it's easy to do
with 'C-x C-w RET', when the default value will be changed to t.