Struct StorageBytes

pub struct StorageBytes { /* private fields */ }

Accessor for storage-backed bytes.

Implementations

impl StorageBytes

pub fn is_empty(&self) -> bool

Returns true if the collection contains no elements.

pub fn len(&self) -> usize

Gets the number of bytes stored.

pub unsafe fn set_len(&mut self, len: usize)

Overwrites the collection’s length, moving bytes as needed.

Safety

May populate the vector with junk bytes from prior dirty operations. Note that StorageBytes has unlimited capacity, so all lengths are valid.

pub fn push(&mut self, value: u8)

Adds a byte to the end.

pub fn pop(&mut self) -> Option<u8>

Removes and returns the last byte, if it exists. As an optimization, underlying storage slots are only erased when all bytes in a given word are freed when in the multi-word representation.

pub fn get(&self, index: impl TryInto<usize>) -> Option<u8>

Gets the byte at the given index, if it exists.

pub fn get_mut( &mut self, index: impl TryInto<usize>, ) -> Option<StorageGuardMut<'_, StorageB8>>

Gets a mutable accessor to the byte at the given index, if it exists.

pub unsafe fn get_unchecked(&self, index: usize) -> u8

Gets the byte at the given index, even if beyond the collection.

Safety

UB if index is out of bounds.

pub fn get_bytes(&self) -> Vec<u8>

Gets the full contents of the collection.

pub fn set_bytes(&mut self, bytes: impl AsRef<[u8]>)

Overwrites the contents of the collection, erasing what was previously stored.

Trait Implementations

impl Erase for StorageBytes

fn erase(&mut self)

Erase the value from persistent storage.

impl<'a> Extend<&'a u8> for StorageBytes

fn extend<T: IntoIterator<Item = &'a u8>>(&mut self, iter: T)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

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

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

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

Reserves capacity in a collection for the given number of additional elements.

impl Extend<u8> for StorageBytes

fn extend<T: IntoIterator<Item = u8>>(&mut self, iter: T)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

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

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

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

Reserves capacity in a collection for the given number of additional elements.

impl<T> From<&T> for StorageBytes

where T: Host + Clone + 'static,

fn from(host: &T) -> Self

Converts to this type from the input type.

impl HostAccess for StorageBytes

fn vm(&self) -> &dyn Host

Provides access to the parametrized host of a contract, giving access to all the desired hostios from the user.

impl StorageType for StorageBytes

type Wraps<'a> = StorageGuard<'a, StorageBytes> where Self: 'a

For primitive types, this is the type being stored. For collections, this is the StorageType being collected.

type WrapsMut<'a> = StorageGuardMut<'a, StorageBytes> where Self: 'a

Mutable accessor to the type being stored.

unsafe fn new(root: U256, offset: u8, host: VM) -> Self

Where in persistent storage the type should live. Although useful for framework designers creating new storage types, most user programs shouldn’t call this. Note: implementations will have to be const once generic_const_exprs stabilizes.

fn load<'s>(self) -> Self::Wraps<'s>

Load the wrapped type, consuming the accessor. Note: most types have a get and/or getter, which don’t consume Self.

fn load_mut<'s>(self) -> Self::WrapsMut<'s>

Load the wrapped mutable type, consuming the accessor. Note: most types have a set and/or setter, which don’t consume Self.

const SLOT_BYTES: usize = 32usize

The number of bytes in a slot needed to represent the type. Must not exceed 32. For types larger than 32 bytes that are stored inline with a struct’s fields, set this to 32 and return the full size in StorageType::new.

const REQUIRED_SLOTS: usize = 0usize

The number of words this type must fill. For primitives this is always 0. For complex types requiring more than one inline word, set this to the total size.