fn generate_split_method(
row_name: &Ident,
variant_infos: &[VariantInfo],
impl_generics: &ImplGenerics<'_>,
ty_generics: &TypeGenerics<'_>,
where_clause: Option<&WhereClause>,
) -> TokenStreamExpand description
Generate the to_dataframe_split associated method for an enum DataFrameRow.
For a single-variant enum, returns the data.frame directly. For multi-variant enums, returns a named R list of data.frames (one per variant, named with snake_case variant names). Each partition data.frame has only that variant’s columns (non-optional types — no NA fill from other variants).