bug#15746: 24.3; [PATCH] bookmark should confirm when overwrite

[Drew Adams]

> >No.  A variable is not user friendly.  There should be two
> >different commands, bound to two different keys.  It is about
> >different use cases - for different contexts.  It is not about
> >different users, some of whom always want silent updating and some
> >of whom always want confirmation querying.
> 
> That's another solution, hmmm, but it seems to me it complexifies
> the user interface a bit 

It's a lot simpler for a user than changing a variable value for one
bookmark update (w/o confirmation) and changing it again for another
update (w/ confirmation).

> (it adds another binding in the keyspace, which the user then cannot
> avoid encountering when looking at the available bound commands

That's a good thing.  Helps users see that both possibilities exist.

> -- whereas a variable is something they only need to deal with
> if/when they go looking for it, read the documentation, etc).

Which is not a thing.  And `C-h m' and `C-h b' *are* part of the
documentation.

> So I'm not sure which way is better; I think we might be down to
> the "tyranny of small differences" at that point :-).

If you take the point of view that both are useful behaviors for a
user to have (even the same user, in different contexts), and that
it should be easy to use either of them, then having two commands
recommends itself as the way to go.  If you don't want to provide
key bindings for both commands, fine (but too bad).

> >Providing a variable as the only means to silently update does
> >not provide equal flexibility.
> >
> >There is no need for a discussion about defaults (except for which
> >command goes on which key), if you provide two different commands
> >bound to two different keys.  And that really *does* provide
> >"equal flexibility".
> 
> As far as that assertion goes, it is true, yes.  It doesn't address
> the keyspace complexity issue.

I don't see a keyspace complexity issue here.  Having both `C-x r m'
and, say, `C-x r M', which do almost the same thing, sounds quite
reasonable, to me.