Struct ckb_fixed_hash::H256

pub struct H256(pub [u8; 32]);

The 32-byte fixed-length binary data.

The name comes from the number of bits in the data.

In JSONRPC, it is encoded as a 0x-prefixed hex string.

Tuple Fields

0: [u8; 32]

Implementations

impl H256

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

Converts Self to a byte slice.

pub fn from_slice(input: &[u8]) -> Result<H256, FromSliceError>

To convert the byte slice back into Self.

impl H256

pub fn from_trimmed_str(input: &str) -> Result<H256, FromStrError>

To convert a trimmed hexadecimal string into Self.

If the beginning of a hexadecimal string are one or more zeros, then these zeros should be omitted.

There should be only one zero at the beginning of a hexadecimal string at most.

For example, if x is H16 (a 16 bits binary data):

• when x = [0, 0], the trimmed hexadecimal string should be “0” or “”.
• when x = [0, 1], the trimmed hexadecimal string should be “1”.
• when x = [1, 0], the trimmed hexadecimal string should be “100”.

use ckb_fixed_hash_core::H256 as Hash;
const BYTES_SIZE: usize = 32;

let mut inner = [0u8; BYTES_SIZE];

{
    let actual = Hash(inner.clone());
    let expected1 = Hash::from_trimmed_str("").unwrap();
    let expected2 = Hash::from_trimmed_str("0").unwrap();
    assert_eq!(actual, expected1);
    assert_eq!(actual, expected2);
}

{
    inner[BYTES_SIZE - 1] = 1;
    let actual = Hash(inner);
    let expected = Hash::from_trimmed_str("1").unwrap();
    assert_eq!(actual, expected);
}

{
    assert!(Hash::from_trimmed_str("00").is_err());
    assert!(Hash::from_trimmed_str("000").is_err());
    assert!(Hash::from_trimmed_str("0000").is_err());
    assert!(Hash::from_trimmed_str("01").is_err());
    assert!(Hash::from_trimmed_str("001").is_err());
    assert!(Hash::from_trimmed_str("0001").is_err());
}

Trait Implementations

impl AsMut<[u8]> for H256

fn as_mut(&mut self) -> &mut [u8]

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

impl AsRef<[u8]> for H256

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

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

impl Clone for H256

fn clone(&self) -> H256

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for H256

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

Formats the value using the given formatter.

impl Default for H256

fn default() -> H256

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for H256

fn deserialize<D>(
    deserializer: D
) -> Result<H256, <D as Deserializer<'de>>::Error>where
    D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for H256

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

Formats the value using the given formatter.

impl From<[u8; 32]> for H256

fn from(bytes: [u8; 32]) -> H256

Converts to this type from the input type.

impl FromStr for H256

type Err = FromStrError

The associated error which can be returned from parsing.

fn from_str(input: &str) -> Result<H256, <H256 as FromStr>::Err>

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

impl Hash for H256

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

Feeds this value into the given Hasher.

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

Feeds a slice of this type into the given Hasher.

impl LowerHex for H256

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

Formats the value using the given formatter.

impl Ord for H256

fn cmp(&self, other: &H256) -> Ordering

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

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

Restrict a value to a certain interval.

impl PartialEq<H256> for H256

fn eq(&self, other: &H256) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

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

impl PartialOrd<H256> for H256

fn partial_cmp(&self, other: &H256) -> Option<Ordering>

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

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

This method tests less than (for self and other) and is used by the < operator.

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

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

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

This method tests greater than (for self and other) and is used by the > operator.

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

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

impl Serialize for H256

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

Serialize this value into the given Serde serializer.

impl Eq for H256