A key is sixteen opaque bytes, rendered as a lowercase dashed UUID.
Integer identities park in the low eight bytes, so Key(42) prints as 00000000-0000-0000-0000-00000000002a and an integer literal is a key wherever one is expected.
Keys need not be unique: several entries may share one, and count(key:) reports how many.
A key is Codable as that same string, so a document written by any SDK reads back here unchanged.
let key: Key = 42
assert(key.integerIdentity == 42)
let parsed = try Key(parsing: key.description) // equal to `key`
let encoded = String(decoding: try JSONEncoder().encode(key), as: UTF8.self) // "\"\(key)\""KeyA 128-bit entry identity, most significant byte first, rendered as a lowercase dashed UUID.7struct KeyKeys need not be unique: several entries may share one, and DenseIndex.count(key:)
reports how many. Integer identities park in the low eight bytes, so Key(42)
prints as 00000000-0000-0000-0000-00000000002a.
Hashable, Comparable, CustomStringConvertible, ExpressibleByIntegerLiteral, Sendable, Equatable, Decodable, EncodablenilKeyThe all-zero key.static let nilKey: KeyinitBuilds the all-zero key.init()init(_ value: UInt64)Parks an integer identity in the low eight bytes, zeroing the rest.
init(integerLiteral value: UInt64)init(bytes: [UInt8]) throws(USearchError)Adopts sixteen bytes, most significant first.
init(parsing text: String) throws(USearchError)Reads the rendering description produces.
init(from decoder: any Decoder) throwsReads the key from the lowercase dashed rendering description produces.
byteArrayThe sixteen identity bytes, most significant first.var byteArray: [UInt8] { get }integerIdentityThe integer identity in the low eight bytes, and nil when the high eight carry anything.var integerIdentity: UInt64? { get }descriptionvar description: String { get }*× 3encodeWrites the key as that same rendering.func encode(to encoder: any Encoder) throws