Struct cw_storage_plus::Map

pub struct Map<'a, K, T> { /* fields omitted */ }

Implementations

impl<'a, K, T> Map<'a, K, T>

pub const fn new(namespace: &'a [u8]) -> Self

impl<'a, K, T> Map<'a, K, T> where
    T: Serialize + DeserializeOwned,
    K: PrimaryKey<'a>, 

pub fn key(&self, k: K) -> Path<T>

pub fn save<S: Storage>(&self, store: &mut S, k: K, data: &T) -> StdResult<()>

pub fn remove<S: Storage>(&self, store: &mut S, k: K)

pub fn load<S: Storage>(&self, store: &S, k: K) -> StdResult<T>

load will return an error if no data is set at the given key, or on parse error

pub fn may_load<S: Storage>(&self, store: &S, k: K) -> StdResult<Option<T>>

may_load will parse the data stored at the key if present, returns Ok(None) if no data there. returns an error on issues parsing

pub fn update<A, E, S>(&self, store: &mut S, k: K, action: A) -> Result<T, E> where
    A: FnOnce(Option<T>) -> Result<T, E>,
    E: From<StdError>,
    S: Storage, 

Loads the data, perform the specified action, and store the result in the database. This is shorthand for some common sequences, which may be useful.

If the data exists, action(Some(value)) is called. Otherwise action(None) is called.

Trait Implementations

impl<'a, K: Clone, T: Clone> Clone for Map<'a, K, T>

fn clone(&self) -> Map<'a, K, T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'a, K: Debug, T: Debug> Debug for Map<'a, K, T>

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

Formats the value using the given formatter.