I've just been reminded of the existence of http://wiki.openstreetmap.org/wiki/Key:demolished
which nobody is using very much, and which nobody seems to be maintaining. I hope nobody will start using it, for it seems to me that this tag will generate bad data: i. If an object is demolished, its other tags should be removed, or at least or "namespaced out" in a matter similar to what we should now be doing for disused=yes and abandoned=yes. Not doing so will confuse map data consumers, creating situations where demolished objects are used for routing or rendering; ii. The date format is Wrong: see http://xkcd.com/1179/ (we should be using partial ISO dates too, in case the day or the month of demolition is not known); iii. We should not in general be mapping features which are no longer physically relevant. Demolished items by their very nature are not relevant, and are potentially not verifiable. OSM a map of the the world as it is in reality, verifiably and currently, and not a historic map. If a demolished item is currently a brownfield site, it should be tagged as a new object with those details. If it's now a construction site, tag it as that. Therefore I propose: a) Modification of this page to avoid bad data creeping into the database, by: 1. Rewriting it as a namespace in a similar manner to abandoned and disused, addressing [i]; 2. Altering the date specification to be Right, namely the ISO 8601 date formats, addressing [ii]. b) Strongly discouraging its use altogether, addressing [iii]. -- Andrew Chadwick _______________________________________________ Tagging mailing list [email protected] http://lists.openstreetmap.org/listinfo/tagging
