Struct HashValue 

pub struct HashValue(/* private fields */);

A 32-byte cryptographic hash value.

Hash values are used throughout Aptos for:

• Transaction hashes
• State roots
• Event keys
• Merkle tree nodes

Example

use aptos_sdk::HashValue;

// Compute a hash
let hash = HashValue::sha3_256(b"hello world");
assert_eq!(hash.to_hex().len(), 66); // "0x" + 64 hex chars

// Parse from hex (64 hex characters)
let hex = "0x0000000000000000000000000000000000000000000000000000000000000001";
let hash = HashValue::from_hex(hex).unwrap();

Implementations

impl HashValue

pub const ZERO: Self

The “zero” hash (all zeros).

pub const fn new(bytes: [u8; 32]) -> Self

Creates a hash from a byte array.

pub fn sha3_256<T: AsRef<[u8]>>(data: T) -> Self

Computes the SHA3-256 hash of the given data.

pub fn sha3_256_of<I, T>(items: I) -> Self

where I: IntoIterator<Item = T>, T: AsRef<[u8]>,

Computes the SHA3-256 hash of multiple byte slices.

pub fn from_hex<T: AsRef<[u8]>>(hex_str: T) -> AptosResult<Self>

Creates a hash from a hex string (with or without 0x prefix).

Errors

Returns an error if the hex string contains invalid UTF-8, is not exactly 64 hex characters (excluding the optional 0x prefix), or contains invalid hex characters.

pub fn from_bytes<T: AsRef<[u8]>>(bytes: T) -> AptosResult<Self>

Creates a hash from a byte slice.

Errors

Returns an error if the byte slice is not exactly 32 bytes long.

pub fn as_bytes(&self) -> &[u8]

Returns the hash as a byte slice.

pub fn to_bytes(&self) -> [u8; 32]

Returns the hash as a byte array.

pub fn to_hex(&self) -> String

Returns the hash as a hex string with 0x prefix.

pub fn is_zero(&self) -> bool

Returns true if this is the zero hash.

Trait Implementations

impl AsRef<[u8]> for HashValue

fn as_ref(&self) -> &[u8]

Converts this type into a shared reference of the (usually inferred) input type.

impl Clone for HashValue

fn clone(&self) -> HashValue

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for HashValue

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

Formats the value using the given formatter.

impl Default for HashValue

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for HashValue

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for HashValue

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

Formats the value using the given formatter.

impl From<[u8; 32]> for HashValue

fn from(bytes: [u8; 32]) -> Self

Converts to this type from the input type.

impl From<HashValue> for [u8; 32]

fn from(hash: HashValue) -> Self

Converts to this type from the input type.

impl FromStr for HashValue

type Err = AptosError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl Hash for HashValue

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for HashValue

fn cmp(&self, other: &HashValue) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for HashValue

fn eq(&self, other: &HashValue) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for HashValue

fn partial_cmp(&self, other: &HashValue) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for HashValue

fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for HashValue

impl Eq for HashValue

impl StructuralPartialEq for HashValue