Trait fuel_vm::prelude::MerkleStorage

pub trait MerkleStorage<P, K, V> where
    V: Clone, {
    type Error: Error;
    fn insert(
        &mut self, 
        parent: &P, 
        key: &K, 
        value: &V
    ) -> Result<Option<V>, Self::Error>;
    fn remove(&mut self, parent: &P, key: &K) -> Result<Option<V>, Self::Error>;
    fn get(
        &'a self, 
        parent: &P, 
        key: &K
    ) -> Result<Option<Cow<'a, V>>, Self::Error>;
    fn contains_key(&self, parent: &P, key: &K) -> Result<bool, Self::Error>;
    fn root(&mut self, parent: &P) -> Result<[u8; 32], Self::Error>;
}

Base trait for Fuel Merkle storage

Generics:

• P: Domain of the merkle tree
• K: Key that maps to a value
• V: Stored value

Associated Types

type Error: Error

Error implementation of the merkle storage functions

Required methods

fn insert(
    &mut self,
    parent: &P,
    key: &K,
    value: &V
) -> Result<Option<V>, Self::Error>

Append P->K->V mapping to the storage.

If K was already mappped to a value, return the replaced value as Ok(Some(V)). Return Ok(None) otherwise.

fn remove(&mut self, parent: &P, key: &K) -> Result<Option<V>, Self::Error>

Remove P->K->V mapping from the storage.

Return Ok(Some(V)) if the value was present. If the key wasn’t found, return Ok(None).

fn get(&'a self, parent: &P, key: &K) -> Result<Option<Cow<'a, V>>, Self::Error>

Retrieve Cow<V> such as P->K->V.

fn contains_key(&self, parent: &P, key: &K) -> Result<bool, Self::Error>

Return true if there is a P->K mapping to a value in the storage.

fn root(&mut self, parent: &P) -> Result<[u8; 32], Self::Error>

Return the merkle root of the domain of P.

The cryptographic primitive is an arbitrary choice of the implementor and this trait won’t impose any restrictions to that.

Implementations on Foreign Types

impl<'_, P, K, V, S> MerkleStorage<P, K, V> for &'_ mut S where
    V: Clone,
    S: MerkleStorage<P, K, V>, 

type Error = <S as MerkleStorage<P, K, V>>::Error

pub fn insert(
    &mut self,
    parent: &P,
    key: &K,
    value: &V
) -> Result<Option<V>, <S as MerkleStorage<P, K, V>>::Error>

pub fn remove(
    &mut self,
    parent: &P,
    key: &K
) -> Result<Option<V>, <S as MerkleStorage<P, K, V>>::Error>

pub fn get(
    &self,
    parent: &P,
    key: &K
) -> Result<Option<Cow<'_, V>>, <S as MerkleStorage<P, K, V>>::Error>

pub fn contains_key(
    &self,
    parent: &P,
    key: &K
) -> Result<bool, <S as MerkleStorage<P, K, V>>::Error>

pub fn root(
    &mut self,
    parent: &P
) -> Result<[u8; 32], <S as MerkleStorage<P, K, V>>::Error>

Implementors

impl MerkleStorage<ContractId, Bytes32, Bytes32> for MemoryStorage

type Error = Infallible

impl MerkleStorage<ContractId, Color, u64> for MemoryStorage

type Error = Infallible