[Geojson] GeometryCollection not treated as a Geometry type

[Martin Daly]

> Well, this got me wondering ... if we can define a geometry using a
> geometry collection (i.e. multiple geometries), are MultiPoint,
> MultiLineString and MultiPolygon redundant?

That is an entirely arbitrary cut-off point.

One could just as easily argue that, because GeometryCollection could
contain a single Geometry, that Point, LineString and Polygon are also
redundant.  It has also been argued, a month or so ago
(http://lists.geojson.org/pipermail/geojson-geojson.org/2007-September/0
00206.html) that Point, LineString and Polygon are redundant because a
single-Geometry MultiPoint, MultiLineString or MultiPolygon is the same
thing, thus ending up with a different, but also arbitrary, subset.

For me, either we have all types (+1, and +compatibility with OGC SF),
or we have one type (-1).

M