fn default_struct_substructure(
cx: &ExtCtxt<'_>,
trait_span: Span,
variant_data: &VariantData,
type_ident: Ident,
) -> BlockOrExprfn default_struct_substructure(
cx: &ExtCtxt<'_>,
trait_span: Span,
variant_data: &VariantData,
type_ident: Ident,
) -> BlockOrExpr