A Key is a 128-bit identity, rendered as a lowercase dashed UUID.
Integer identities park in the low eight bytes, so Key::from(42u64) prints as 00000000-0000-0000-0000-00000000002a.
let key = Key::from(42u64);
let wide = Key::from(0x0123_4567_89ab_cdef_0123_4567_89ab_cdefu128);
let parsed: Key = "00000000-0000-0000-0000-00000000002a".parse()?;
assert_eq!(u64::try_from(parsed), Ok(42)); // refused when the high eight bytes are set
assert_eq!(u128::from(wide), 0x0123_4567_89ab_cdef_0123_4567_89ab_cdef);Keys need not be unique: an index admits up to values_per_key entries under one, count reports how many it holds, and get returns them all. Key::NIL is the all-zero key.
KeyA 128-bit entry identity, rendered as a lowercase dashed UUID.1pub struct Key(pub [u8; 16]);Keys need not be unique: several entries may share one, and count reports how many.
Integer identities park in the low eight bytes, so Key::from(42u64) prints as
00000000-0000-0000-0000-00000000002a.
0 | [u8; 16] | The sixteen identity bytes, most significant first. |
|---|
NILThe all-zero key.pub const NIL: Key = _;