Re: The `risky-local-variable' blacklist

[Richard Stallman]

    In summary, in my Emacs (21.3.1) "emacs -q --no-site-file" yields only 498
    non-risky user variables (as tested by `user-variable-p', `boundp', and
    `risky-local-variable-p'), 

Does this 498 include only variables that are preloaded or autoloaded?
I would guess so.  The actual number of user-option variables defined 
in Lisp files must be much larger.

To pick the first example I could find, does that 498 include
makefile-macro-assign?  That variable is safe.

    > Here's an idea that might do the job and be acceptable.  Each time
    > Emacs sees a variable/value combination that is new for the current
    > user, it asks the user to confirm that combination.  Any given
    > combination only needs to be confirmed once by any given user.  This
    > could reduce the repetitive nuisance down to the point where people
    > will (1) accept the burden and (2) not zone out when they see the
    > questions.
    >
    > What do you think?

    That sounds like it would work, but it also sounds like a lot of overhead 
    (and more user-data to keep up with in one dot-file or another); since 
    users could of course put `safe-local-variable' declarations into their 
    .emacs, it might not be necessary.  Combined with the arbitrary filter 
    feature (where the `safe-local-variable' property stores a check-function 
    through which to run the file's value for the variable) and a simple 
    interface (like that provided for disabled commands), my original 
    suggestion would be almost entirely equivalent.

As regards the work we would have to do, they are not even similar.
One involves studying every variable.  The other does not.