Advanced fields

Advanced fields occupy one packed slot in a struct. Pass a factory (c.Bool, c.String, c.Time64, …) or an instance to @c.field. Multi-field layouts should use @c.struct instead.

Built-in types

Type	Guide
Custom c.AdvancedType	Custom types
c.Bool()	Boolean
c.String(n)	Latin-1 string
c.WString(n)	Wide string
c.Time64()	Unix time
c.bitfield(storage, flags)	Bitfield

Factories: c.Bool, c.String, c.WString, c.Time64, and c.bitfield. Classes: c.CBool, c.CString, c.CWString, c.CTime64, and c.CBitfield (same wire format; use for instanceof checks).

Full struct example

TypeScript layout from Example structures and the matching C mental model:

@c.struct()
class ContentItemHistory {
  @c.field(c.Time64())
  timestamp!: Date;

  @c.field("u64")
  xuid!: bigint;

  @c.field(c.String(16))
  name!: string;

  @c.field("u8", { pad_after: 3 })
  is_online!: number; /* pad_after mirrors C trailing padding for 4-byte alignment */
}

#pragma pack(push, 4)

typedef struct {
    uint64_t timestamp;   /* c.Time64() — offset 0 */
    uint64_t xuid;        /* c.field("u64") — offset 8 */
    char     name[16];    /* c.String(16) — offset 16 */
    uint8_t  is_online;   /* c.field("u8") — offset 32 */
    /* 3 bytes implicit padding (offsets 33–35); compiler inserts this
       so sizeof(ContentItemHistory) is a multiple of 4 (36 bytes total) */
} ContentItemHistory;

#pragma pack(pop)

The explicit pad_after: 3 in TypeScript matches those three alignment bytes — you are not reserving a separate named _pad field in the on-disk layout.