Hash32

Hash32<T> = Callable<[T, number], number>

Defined in: packages/data/src/probabilistic/hash32.ts:28

Hashes an item to a 32-bit unsigned integer.

Required, never defaulted: hashes — murmur3_32, xxhash_32, fnv_32, djb2 — all take a Uint8Array, and there is no canonical way to turn an arbitrary T into bytes. Only the caller knows how its items should be encoded, so only the caller can close that gap:

import { murmur3_32 } from "@ac-kit/noncrypto-hash";

const encoder = new TextEncoder();
const hash: Hash32<string> = (item, seed) =>
  murmur3_32(encoder.encode(item), seed);

The quality of the estimate is the quality of this function. It must distribute uniformly and avalanche — a weak hash does not merely degrade the false-positive rate, it invalidates the arithmetic these structures are derived from.

Type Parameters

T

T

Param

item

The item to hash.

Param

seed

A per-call seed. The same (item, seed) pair must always give the same result.