The available trivial, native content types of a column.
More complex types, such as classes, get translated into columns of such simple types by the RField. When changed, remember to update
- RColumnElement::Generate()
- RColumnElement::GetTypeName()
- RColumnElement::GetValidBitRange()
- RColumnElement template specializations / packing & unpacking
- If necessary, endianess handling for the packing + unit test in ntuple_endian
- RNTupleSerializer::[Des|S]erializeColumnType