Struct InputHasher 

pub struct InputHasher { /* private fields */ }

Hashes a model’s input for Provenance::input_hash, so an audit can confirm that two results came from the same data.

Each field is written as a one-byte type tag, a little-endian u64 length, then the payload, so neither field boundaries nor types can be confused: str("ab").str("c") differs from str("a").str("bc"), and u64(1) from i64(1). Floats are hashed by their bits, with -0.0 written as 0.0 and every NaN as one canonical NaN, so numerically equal inputs hash equal.

use prospicio_prob::provenance::InputHasher;

let a = InputHasher::new().str("origin").f64s(&[100.0, 150.0]).finish();
let b = InputHasher::new().str("origin").f64s(&[100.0, 150.0]).finish();
assert_eq!(a, b);
assert!(a.starts_with("blake3:"));
assert_ne!(a, InputHasher::new().str("origin").f64s(&[100.0, 151.0]).finish());

Implementations

impl InputHasher

pub fn new() -> Self

An empty hasher keyed by INPUT_HASH_CONTEXT.

pub fn bytes(&mut self, bytes: &[u8]) -> &mut Self

Adds raw bytes, e.g. an Arrow IPC buffer.

pub fn str(&mut self, text: &str) -> &mut Self

Adds UTF-8 text, e.g. a column or dimension name.

pub fn u64(&mut self, value: u64) -> &mut Self

Adds an unsigned integer.

pub fn i64(&mut self, value: i64) -> &mut Self

Adds a signed integer.

pub fn f64s(&mut self, values: &[f64]) -> &mut Self

Adds a sequence of floats; the length is the number of values.

pub fn finish(&self) -> String

The hash of everything added so far, as "blake3:" followed by 64 hex digits. The hasher can keep taking fields afterwards.

Trait Implementations

impl Clone for InputHasher

fn clone(&self) -> InputHasher

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for InputHasher

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for InputHasher

fn default() -> Self

Returns the “default value” for a type.