Struct Persistent

pub struct Persistent { /* private fields */ }

Implementations

impl Persistent

pub fn has<K>(&self, key: &K) -> bool

where K: IntoVal<Env, Val>,

pub fn get<K, V>(&self, key: &K) -> Option<V>

where V::Error: Debug, K: IntoVal<Env, Val>, V: TryFromVal<Env, Val>,

pub fn set<K, V>(&self, key: &K, val: &V)

where K: IntoVal<Env, Val>, V: IntoVal<Env, Val>,

pub fn update<K, V>(&self, key: &K, f: impl FnOnce(Option<V>) -> V) -> V

where K: IntoVal<Env, Val>, V: IntoVal<Env, Val> + TryFromVal<Env, Val>,

Update a value stored against a key.

Loads the value, calls the function with it, then sets the value to the returned value of the function. If no value is stored with the key then the function is called with None.

The returned value is the value stored after updating.

pub fn try_update<K, V, E>( &self, key: &K, f: impl FnOnce(Option<V>) -> Result<V, E>, ) -> Result<V, E>

where K: IntoVal<Env, Val>, V: IntoVal<Env, Val> + TryFromVal<Env, Val>,

Update a value stored against a key.

Loads the value, calls the function with it, then sets the value to the returned value of the function. If no value is stored with the key then the function is called with None. If the function returns an error it will be passed through.

The returned value is the value stored after updating.

pub fn extend_ttl<K>(&self, key: &K, threshold: u32, extend_to: u32)

where K: IntoVal<Env, Val>,

Extend the TTL of the data under the key.

Extends the TTL only if the TTL for the provided data is below threshold ledgers. The TTL will then become extend_to.

The TTL is the number of ledgers between the current ledger and the final ledger the data can still be accessed.

pub fn remove<K>(&self, key: &K)

where K: IntoVal<Env, Val>,

Trait Implementations

impl Persistent for Persistent

Available on crate feature testutils only.

fn all(&self) -> Map<Val, Val>

Returns all data stored in persistent storage for the contract.

fn get_ttl<K: IntoVal<Env, Val>>(&self, key: &K) -> u32

Gets the TTL for the persistent storage entry corresponding to the provided key.