A 1d shape, a line, cannot have a hyperperimeter; there simply is no property of the line that could be called a hyperperimeter. The hyperperimeter is one dimension below the hyperarea of the shape, so a hyperperimeter of a line would be measured in meters (or insert other length unit) to the zeroth power - a dimensionless quantity which is always equal to one. A point is a zero-dimensional shape, so its volume is dimensionless, and its hyperperimeter would be measured in meters to the minus one, for example one per meter, even more nonsensical!
There is no value you can assign to the hyperperimeter of a line or to the hyperperimeter or hyperarea of a point because these shapes inherently cannot have these properties, so the only sensible course of action is to return (length, None) or (None, None) in their place.