Struct SingleFieldData 

struct SingleFieldData {
    rust_name: Ident,
    col_name: Ident,
    col_name_str: String,
    ty: Type,
    tuple_index: Option<Index>,
    needs_into_list: bool,
    list_elem_ty: Option<Type>,
    map_reader: bool,
}

Data for ResolvedField::Single.

Fields

rust_name: Ident

Rust field name (for access).

col_name: Ident

Column name in the DataFrame.

col_name_str: String

Column name string.

ty: Type

Field type stored in the companion Vec<#ty>. For #[dataframe(as_list)] on a struct-typed field this is overridden to ::miniextendr_api::list::List — see needs_into_list.

tuple_index: Option<Index>

Index in tuple struct (None for named).

needs_into_list: bool

#[dataframe(as_list)] on a struct-typed field (#485 workaround). When true, the companion field type is overridden to List and From<Vec<Row>> calls IntoList::into_list() on each row value.

list_elem_ty: Option<Type>

Some(elem) when this Single field is an un-annotated owned collection (Vec<scalar> / Box<[scalar]>) stored as an opaque list-column (#809). The reader deserialises the list-column back into the owned collection per row via Vec<elem>: TryFromSexp then .into() to the field container type. None for scalar Single, as_list, opaque Map/set columns, and borrowed &[T] (not readable).

map_reader: bool

true when this Single field is a reader-capable map column (#764): HashMap<String, V> / BTreeMap<String, V> with a reader-scalar V and no custom hasher. The column is read whole as Vec<#ty> via the Vec<map>: TryFromSexp list-of-named-lists impl — the same pull_col path scalar Singles use, so it only widens the capability gate.

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 752 bytes