To give it a shot I try to add variant support to "distance" taking
"correct" as an example. Binary operation are more challenging since
support for combinations (variant, variant), (non-variant, variant),
(variant, non-variant) needs to be implemented.
Moreover, if the variant
has 2d and 3d points, the dimension of both geometry must be checked to
be the same.
That raise the question how to report runtime errors ?
Does that mean that we can dispatch incompatible variant to a runtime
error using not_yet_implemented ? That would be brilliant !