Our group has already received a request from @paulc-dstl to add GeoHash literals to GeoSPARQL.

However, there are more geocoding systems which could be taken into account here.

In fact, a lot of geocoding systems can be resolved to coordinates in either UTM or WGS84-based coordinate reference systems.

My question here:

Would it make sense to maybe define two literal types: "wgs84GeocodingLiteral" and "utmGeoCodingLiteral" and indicate the Geocoding system with a URI definition, similar to how we do it in WKT?

WGS84-based Open Geocoding Systems:

• GeoHash
• MapCode
• Natural Area Code
• Open Location Code

We could curate a list of URIs for well-known geocoding systems which implementers could use.

Or should we proceed with defining GeoHash, and people should create their own literal types outside the standard?