fn expand_struct(
attr: TokenStream,
item: TokenStream,
item_struct: &ItemStruct,
) -> TokenStreamExpand description
Dispatches #[miniextendr] on a struct to the correct derive path.
Decision logic:
- 1-field struct with no explicit mode: ALTREP (backwards compatibility)
- Explicit
listmode:IntoList+TryFromList+PreferList - Explicit
dataframemode:IntoList+DataFrameRow+ companionIntoR - Default multi-field or explicit
externalptr:ExternalPtr prefer = "native":ExternalPtr+PreferRNativemarker