[Tagging] tagging for decaying features

[Warin]

On 04-Jan-18 06:49 AM, yo paseopor wrote:
> No, In my opinion is not a good idea to delete an existing thing in 
> OSM. History is also part of OSM. Why do we have to respect the 
> historic thing in a node or way not deleting them if then we then 
> delete the whole thing.

I am saying 'historic' is not part of the life cycle. I am not deleting 
it from OSM .. but moving it out of the 'life cycle' category.

> Lifecycle prefix can achieve these items inside OSM. Also it is not a 
> good idea to expulse the information to other third or related 
> projects...that one day can be gone. Because if the info is in OSM one 
> day other related project can recover the map with that data (e.g. 
> parking map). If the information is in other related project, when the 
> project dies (as Mapzen for example) , information dies too.

OSM could die too. So where would the data be then?

Using OHM to record the historic data should be fine.

I have moved some disused:railway=* from OSM to OHM as railway=* with 
start and end dates .. that records what was there then, not its present 
state ...
Some of this 'disused:railway' is now gone .. built over by roads, 
houses factories and holes in the ground. It is not there in any way 
other than memory.
Some of it has been removed, but you can see where it was.

My difficulty is in tagging these various states - beyond abandoned: .. 
to me there are 2 further states;
  - a ruin or ruins or ruined.
- no longer there - non_existent. Presently used tags of 'removed' and 
'demolished' have implications as to how the thing was made non 
existent, and that I don't know.

> If the info disturb one good idea would be change osm-carto, the 
> render, but no the database as it is not a good idea in other 
> situations. We don't map for the render.
Do we map what is not there? Ghosts or the past?

What is OSM for? To me navigation - what is there on the ground now so I 
can use that to navigate by.
So things that are gone would be simply clutter and have no relevance.
And things that are visible I would like rendered.