Function struct_encode_helper

arrow-row/src/lib.rs:1939–1973

(
                array: &StructArray,
                offsets: &mut [usize],
                null_sentinel: u8,
                rows: &Rows,
                null: &Row<'_>,
                data: &mut

        }
        Encoder::Struct(rows, null) => {
            fn struct_encode_helper<const NO_CHILD_FIELDS: bool>(
                array: &StructArray,
                offsets: &mut [usize],
                null_sentinel: u8,
                rows: &Rows,
                null: &Row<'_>,
                data: &mut [u8],
            ) {
                let empty_row = Row {
                    data: &[],
                    config: &rows.config,
                };

                offsets
                    .iter_mut()
                    .skip(1)
                    .enumerate()
                    .for_each(|(idx, offset)| {
                        let (row, sentinel) = match array.is_valid(idx) {
                            true => (
                                if NO_CHILD_FIELDS {
                                    empty_row
                                } else {
                                    rows.row(idx)
                                },
                                0x01,
                            ),
                            false => (*null, null_sentinel),
                        };
                        let end_offset = *offset + 1 + row.as_ref().len();
                        data[*offset] = sentinel;
                        data[*offset + 1..end_offset].copy_from_slice(row.as_ref());
                        *offset = end_offset;
                    })
            }

            let array = as_struct_array(column);
            let null_sentinel = null_sentinel(opts);