Struct Piece

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

A piece of archival history in Subspace Network.

This version is allocated on the heap, for stack-allocated piece see PieceArray.

Internally piece contains a record and corresponding witness that together with segment commitment of the segment this piece belongs to can be used to verify that a piece belongs to the actual archival history of the blockchain.

Implementations

impl Piece

pub const SIZE: usize = 1_048_672usize

Size of a piece (in bytes).

pub fn to_shared(self) -> Self

Ensure piece contains cheaply cloneable shared data.

Internally piece uses CoW mechanism and can store either mutable owned data or data that is cheap to clone, calling this method will ensure further clones will not result in additional memory allocations.

Methods from Deref<Target = PieceArray>

pub fn split(&self) -> (&Record, &RecordCommitment, &RecordWitness)

Split piece into underlying components.

pub fn split_mut( &mut self, ) -> (&mut Record, &mut RecordCommitment, &mut RecordWitness)

Split piece into underlying mutable components.

pub fn record(&self) -> &Record

Record contained within a piece.

pub fn record_mut(&mut self) -> &mut Record

Mutable record contained within a piece.

pub fn commitment(&self) -> &RecordCommitment

Commitment contained within a piece.

pub fn commitment_mut(&mut self) -> &mut RecordCommitment

Mutable commitment contained within a piece.

pub fn witness(&self) -> &RecordWitness

Witness contained within a piece.

pub fn witness_mut(&mut self) -> &mut RecordWitness

Mutable witness contained within a piece.

Methods from Deref<Target = [u8; 1048672]>

pub fn as_ascii(&self) -> Option<&[AsciiChar; N]>

🔬This is a nightly-only experimental API. (ascii_char)

Converts this array of bytes into an array of ASCII characters, or returns None if any of the characters is non-ASCII.

Examples

#![feature(ascii_char)]

const HEX_DIGITS: [std::ascii::Char; 16] =
    *b"0123456789abcdef".as_ascii().unwrap();

assert_eq!(HEX_DIGITS[1].as_str(), "1");
assert_eq!(HEX_DIGITS[10].as_str(), "a");

pub unsafe fn as_ascii_unchecked(&self) -> &[AsciiChar; N]

🔬This is a nightly-only experimental API. (ascii_char)

Converts this array of bytes into an array of ASCII characters, without checking whether they’re valid.

Safety

Every byte in the array must be in 0..=127, or else this is UB.

pub fn as_slice(&self) -> &[T]

Returns a slice containing the entire array. Equivalent to &s[..].

pub fn as_mut_slice(&mut self) -> &mut [T]

Returns a mutable slice containing the entire array. Equivalent to &mut s[..].

pub fn each_ref(&self) -> [&T; N]

Borrows each element and returns an array of references with the same size as self.

Example

let floats = [3.1, 2.7, -1.0];
let float_refs: [&f64; 3] = floats.each_ref();
assert_eq!(float_refs, [&3.1, &2.7, &-1.0]);

This method is particularly useful if combined with other methods, like map. This way, you can avoid moving the original array if its elements are not Copy.

let strings = ["Ferris".to_string(), "♥".to_string(), "Rust".to_string()];
let is_ascii = strings.each_ref().map(|s| s.is_ascii());
assert_eq!(is_ascii, [true, false, true]);

// We can still access the original array: it has not been moved.
assert_eq!(strings.len(), 3);

pub fn each_mut(&mut self) -> [&mut T; N]

Borrows each element mutably and returns an array of mutable references with the same size as self.

Example

let mut floats = [3.1, 2.7, -1.0];
let float_refs: [&mut f64; 3] = floats.each_mut();
*float_refs[0] = 0.0;
assert_eq!(float_refs, [&mut 0.0, &mut 2.7, &mut -1.0]);
assert_eq!(floats, [0.0, 2.7, -1.0]);

pub fn split_array_ref<const M: usize>(&self) -> (&[T; M], &[T])

🔬This is a nightly-only experimental API. (split_array)

Divides one array reference into two at an index.

The first will contain all indices from [0, M) (excluding the index M itself) and the second will contain all indices from [M, N) (excluding the index N itself).

Panics

Panics if M > N.

Examples

#![feature(split_array)]

let v = [1, 2, 3, 4, 5, 6];

{
   let (left, right) = v.split_array_ref::<0>();
   assert_eq!(left, &[]);
   assert_eq!(right, &[1, 2, 3, 4, 5, 6]);
}

{
    let (left, right) = v.split_array_ref::<2>();
    assert_eq!(left, &[1, 2]);
    assert_eq!(right, &[3, 4, 5, 6]);
}

{
    let (left, right) = v.split_array_ref::<6>();
    assert_eq!(left, &[1, 2, 3, 4, 5, 6]);
    assert_eq!(right, &[]);
}

pub fn split_array_mut<const M: usize>(&mut self) -> (&mut [T; M], &mut [T])

🔬This is a nightly-only experimental API. (split_array)

Divides one mutable array reference into two at an index.

The first will contain all indices from [0, M) (excluding the index M itself) and the second will contain all indices from [M, N) (excluding the index N itself).

Panics

Panics if M > N.

Examples

#![feature(split_array)]

let mut v = [1, 0, 3, 0, 5, 6];
let (left, right) = v.split_array_mut::<2>();
assert_eq!(left, &mut [1, 0][..]);
assert_eq!(right, &mut [3, 0, 5, 6]);
left[1] = 2;
right[1] = 4;
assert_eq!(v, [1, 2, 3, 4, 5, 6]);

pub fn rsplit_array_ref<const M: usize>(&self) -> (&[T], &[T; M])

🔬This is a nightly-only experimental API. (split_array)

Divides one array reference into two at an index from the end.

The first will contain all indices from [0, N - M) (excluding the index N - M itself) and the second will contain all indices from [N - M, N) (excluding the index N itself).

Panics

Panics if M > N.

Examples

#![feature(split_array)]

let v = [1, 2, 3, 4, 5, 6];

{
   let (left, right) = v.rsplit_array_ref::<0>();
   assert_eq!(left, &[1, 2, 3, 4, 5, 6]);
   assert_eq!(right, &[]);
}

{
    let (left, right) = v.rsplit_array_ref::<2>();
    assert_eq!(left, &[1, 2, 3, 4]);
    assert_eq!(right, &[5, 6]);
}

{
    let (left, right) = v.rsplit_array_ref::<6>();
    assert_eq!(left, &[]);
    assert_eq!(right, &[1, 2, 3, 4, 5, 6]);
}

pub fn rsplit_array_mut<const M: usize>(&mut self) -> (&mut [T], &mut [T; M])

🔬This is a nightly-only experimental API. (split_array)

Divides one mutable array reference into two at an index from the end.

The first will contain all indices from [0, N - M) (excluding the index N - M itself) and the second will contain all indices from [N - M, N) (excluding the index N itself).

Panics

Panics if M > N.

Examples

#![feature(split_array)]

let mut v = [1, 0, 3, 0, 5, 6];
let (left, right) = v.rsplit_array_mut::<4>();
assert_eq!(left, &mut [1, 0]);
assert_eq!(right, &mut [3, 0, 5, 6][..]);
left[1] = 2;
right[1] = 4;
assert_eq!(v, [1, 2, 3, 4, 5, 6]);

Trait Implementations

impl AsMut<[u8]> for Piece

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

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

impl AsRef<[u8]> for Piece

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

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

impl Clone for Piece

fn clone(&self) -> Piece

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Piece

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

Formats the value using the given formatter.

impl Decode for Piece

fn decode<I: Input>(input: &mut I) -> Result<Self, Error>

Attempt to deserialise the value from input.

fn decode_into<I>( input: &mut I, dst: &mut MaybeUninit<Self>, ) -> Result<DecodeFinished, Error>

where I: Input,

Attempt to deserialize the value from input into a pre-allocated piece of memory.

fn skip<I>(input: &mut I) -> Result<(), Error>

where I: Input,

Attempt to skip the encoded value from input.

fn encoded_fixed_size() -> Option<usize>

Returns the fixed encoded size of the type.

impl Default for Piece

fn default() -> Self

Returns the “default value” for a type.

impl Deref for Piece

type Target = PieceArray

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl DerefMut for Piece

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<'de> Deserialize<'de> for Piece

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

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Encode for Piece

fn size_hint(&self) -> usize

If possible give a hint of expected size of the encoding.

fn encode_to<O: Output + ?Sized>(&self, output: &mut O)

Convert self to a slice and append it to the destination.

fn encode(&self) -> Vec<u8>

Convert self to an owned vector.

fn using_encoded<R, F: FnOnce(&[u8]) -> R>(&self, f: F) -> R

Convert self to a slice and then invoke the given closure with it.

fn encoded_size(&self) -> usize

Calculates the encoded size.

impl From<&PieceArray> for Piece

fn from(value: &PieceArray) -> Self

Converts to this type from the input type.

impl From<Piece> for Vec<u8>

fn from(piece: Piece) -> Self

Converts to this type from the input type.

impl Hash for Piece

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 PartialEq for Piece

fn eq(&self, other: &Piece) -> 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 Serialize for Piece

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

where S: Serializer,

Serialize this value into the given Serde serializer.

impl TryFrom<&[u8]> for Piece

type Error = ()

The type returned in the event of a conversion error.

fn try_from(slice: &[u8]) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<Bytes> for Piece

type Error = ()

The type returned in the event of a conversion error.

fn try_from(bytes: Bytes) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<BytesMut> for Piece

type Error = ()

The type returned in the event of a conversion error.

fn try_from(bytes: BytesMut) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<Vec<u8>> for Piece

type Error = ()

The type returned in the event of a conversion error.

fn try_from(vec: Vec<u8>) -> Result<Self, Self::Error>

Performs the conversion.

impl TypeInfo for Piece

type Identity = Piece

The type identifying for which type info is provided.

fn type_info() -> Type

Returns the static type identifier for Self.

impl EncodeLike for Piece

impl Eq for Piece

impl StructuralPartialEq for Piece