fn raw_variant_column_error(ty: &Type, padded: bool) -> Option<Error>Expand description
Reject u8 in every variant-field shape that reaches a column: a scalar or
Option<u8>, a fixed array, or a width / expand (padded) slice. Variant columns
are NA in rows of the other variants, and R raw vectors have no NA. A plain
Vec<u8> stays an opaque list-column and is accepted.