pub fn derive_prefer_data_frame(input: DeriveInput) -> Result<TokenStream>Expand description
Derive PreferDataFrame: emits an IntoR impl that converts to R via
ColumnSource::into_column_list, then into_sexp.
The type must implement ColumnSource (typically the companion struct generated
by #[derive(DataFrameRow)]). The generated IntoR::Error is Infallible.