[Tagging] Street and Sub-Street in Address Tagging

[Sarah Hoffmann]

On Sat, Jan 16, 2021 at 04:49:33PM +0100, Colin Smale wrote:
> > We have partial kluges for all three categories, but none work 
> > well.  A field for dependent thoroughfare would be a full solution 
> > for all of them (but there are probably weirder examples that not 
> > even that would fix).
> 
> Indeed, the suggestion of addr:street mapping to the Dependent
> Thoroughfare and addr:parentstreet mapping to the Thoroughfare fixes
> this, and because it is a direct mapping to the address model used by RM
> in the PAF, it is likely to accommodate the "thoroughfare" part of all
> official addresses in the UK. 

The problem I see here is that RoyalMail lumps two very different
concepts into its system of Thoroughfares and Dependent Thoroughfares.

The one kind of cases you have presented are essentially buildings that
get their own numbering. Something like:
https://www.openstreetmap.org/way/736757638 or
https://www.openstreetmap.org/node/5796920749
'Dependent Thoroughfares' is rather a misnomer for them because
the address part is not a street. 

Then there are the other cases, where there is really a side street
that gets the extra house numbers. Example:
https://www.openstreetmap.org/way/407498132

Instead of finding a single addressing schema to fit the RM address in,
I would suggest to handle these two cases differently.

Personally, I'd be pragmatic and just use addr:housename + addr:housenumber
for the first case. The other possibility would be to explicitly allow
addr:place and addr:street to go together and define that in that case
the housenumber refers to the given place but the street must show up
in the address.

For the second case, addr:street + addr:parentstreet makes more sense. It
might not have been my choice of words but being used already is an argument.
It might be worth looking around if the concept of two streets in the address
is used anywhere else in the world. I don't remember that it has ever come
up so far.

Sarah