[Tagging] area=yes on polygones (was Block names)

[Anthony]

On Sat, Apr 28, 2012 at 9:16 AM, Tobias Knerr <osm at tobias-knerr.de> wrote:
> Right now, we already have to distinguish three types of tags:
> * always area
> * always way
> * way unless area=yes is present.
>
> I simply do not think that the possibility to decrease of the number of
> tags is worth introducing "area unless area=no is present" in addition
> to these. Particularly because whether area or way is the default would
> depend on what is assumed to be more likely in reality. And people might
> easily have different assumptions here, making that kind of default
> non-obvious.

I don't see how we'd be adding any more confusion by adding a fourth
type.  Right now if someone tags something as railway=platform they
have to figure out whether it is "always area" (*) or "way unless
area=yes is present", and this is not at all obvious.

Even more confusing are the barrier=* tags.  I think they are of the
type "always way", but I'm not 100% sure about that.  The wiki lists
barrier=city_wall as being a way or an area.  But I think by area they
just mean closed way.  Is barrier=city_wall "always area" (*), "always
way" or "way unless area=yes is present"?  How is someone supposed to
figure this out?

Allowing area=no provides a simple method of dealing with cases where
you are unsure: just tag area=yes/no explicitly.

(*) I note, here, that "always area" doesn't mean "the way always
represents an area", it means "the way always represents an area when
it is closed".