Trait TryCacheStore

pub trait TryCacheStore {
    type Key;
    type Value;
    type Error;

    // Required methods
    fn try_get(
        &self,
        key: impl Borrow<Self::Key>,
    ) -> Result<Option<Self::Value>, Self::Error>;
    fn try_set(
        &mut self,
        key: impl Borrow<Self::Key>,
        value: impl Borrow<Self::Value>,
    ) -> Result<(), Self::Error>;

    // Provided method
    fn try_exists(
        &self,
        key: impl Borrow<Self::Key>,
    ) -> Result<bool, Self::Error> { ... }
}

Trait for a fallible cache store, analogous to CacheStore

Required Associated Types

type Key

type Value

type Error

Required Methods

fn try_get( &self, key: impl Borrow<Self::Key>, ) -> Result<Option<Self::Value>, Self::Error>

Attempts to return an option of the owned cache element if present

fn try_set( &mut self, key: impl Borrow<Self::Key>, value: impl Borrow<Self::Value>, ) -> Result<(), Self::Error>

Attempts to set a value given its key.

Provided Methods

fn try_exists(&self, key: impl Borrow<Self::Key>) -> Result<bool, Self::Error>

Attempts to check if the cache key entry exists.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<K, V, E, A, FnErr: Into<E>, S, F: Fn(&K, A) -> Result<V, FnErr>> TryCacheStore for TryGenCacheStoreWrapper<K, V, E, A, FnErr, S, F>

where S: TryCacheStore + TryCacheStore<Key = K, Value = V, Error = E>,

type Key = <S as TryCacheStore>::Key

type Value = <S as TryCacheStore>::Value

type Error = <S as TryCacheStore>::Error

impl<K, V, E, ET: From<E>, S: TryCacheStore<Key = K, Value = V, Error = E>> TryCacheStore for TryCacheStoreErrorMap<K, V, E, ET, S>

type Key = K

type Value = V

type Error = ET

impl<T: CacheStore> TryCacheStore for T

Allow any CacheStore to behave as a TryCacheStore that never fails.

type Key = <T as CacheStore>::Key

type Value = <T as CacheStore>::Value

type Error = Infallible