Struct cw_storage_plus::UniqueIndex

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

UniqueIndex stores (namespace, index_name, idx_value) -> {key, value} Allows one value per index (i.e. unique) and copies pk and data

Implementations

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

pub fn new(idx_fn: fn(_: &T) -> K, idx_namespace: &'a str) -> Self

Create a new UniqueIndex

idx_fn - lambda creating index key from index value idx_namespace - prefix for the index value

Example:

use cw_storage_plus::{U32Key, UniqueIndex};

struct Data {
    pub name: String,
    pub age: u32,
}

UniqueIndex::new(|d: &Data| U32Key::new(d.age), "data__age");

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

pub fn index_key(&self, k: K) -> Vec<u8>

pub fn prefix(&self, p: K::Prefix) -> Prefix<Vec<u8>, T>

pub fn sub_prefix(&self, p: K::SubPrefix) -> Prefix<Vec<u8>, T>

pub fn item(&self, store: &dyn Storage, idx: K) -> StdResult<Option<Record<T>>>

returns all items that match this secondary index, always by pk Ascending

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

pub fn range<'c>(
    &self,
    store: &'c dyn Storage,
    min: Option<Bound>,
    max: Option<Bound>,
    order: Order
) -> Box<dyn Iterator<Item = StdResult<Record<T>>> + 'c> where
    T: 'c, 

pub fn keys<'c>(
    &self,
    store: &'c dyn Storage,
    min: Option<Bound>,
    max: Option<Bound>,
    order: Order
) -> Box<dyn Iterator<Item = Vec<u8>> + 'c>

Trait Implementations

impl<'a, K, T> Index<T> for UniqueIndex<'a, K, T> where
    T: Serialize + DeserializeOwned + Clone,
    K: PrimaryKey<'a>, 

fn save(&self, store: &mut dyn Storage, pk: &[u8], data: &T) -> StdResult<()>

fn remove(
    &self,
    store: &mut dyn Storage,
    _pk: &[u8],
    old_data: &T
) -> StdResult<()>