Module frame_support::storage::types

Storage types to build abstraction on storage, they implements storage traits such as StorageMap and others.

Structs

• CountedStorageMap
  A wrapper around a StorageMap and a StorageValue<Value=u32> to keep track of how many items are in a map, without needing to iterate all the values.
• CountedStorageNMap
  A wrapper around a StorageNMap and a StorageValue<Value=u32> to keep track of how many items are in a map, without needing to iterate over all of the values.
• Key
  A type used exclusively by storage maps as their key type.
• OptionQuery
  Implement QueryKindTrait with query being Option<Value>
• ResultQuery
  Implement QueryKindTrait with query being Result<Value, PalletError>
• StorageDoubleMap
  A type that allow to store values for (key1, key2) couple. Similar to StorageMap but allow to iterate and remove value associated to first key.
• StorageMap
  A type that allow to store value for given key. Allowing to insert/remove/iterate on values.
• StorageNMap
  A type that allow to store values for an arbitrary number of keys in the form of (Key<Hasher1, key1>, Key<Hasher2, key2>, ..., Key<HasherN, keyN>).
• StorageValue
  A type that allow to store a value.
• ValueQuery
  Implement QueryKindTrait with query being Value

Traits

• CountedStorageMapInstance
  The requirement for an instance of CountedStorageMap.
• CountedStorageNMapInstance
  The requirement for an instance of CountedStorageNMap.
• EncodeLikeTuple
  Marker trait to indicate that each element in the tuple encodes like the corresponding element in another tuple.
• HasKeyPrefix
  Trait indicating whether a KeyGenerator has the prefix P.
• HasReversibleKeyPrefix
  Trait indicating whether a ReversibleKeyGenerator has the prefix P.
• KeyGenerator
  A trait that contains the current key as an associated type.
• KeyGeneratorMaxEncodedLen
  The maximum length used by the key in storage.
• QueryKindTrait
  Trait implementing how the storage optional value is converted into the queried type.
• ReversibleKeyGenerator
  A trait that indicates the hashers for the keys generated are all reversible.
• StorageEntryMetadataBuilder
  Build the metadata of a storage.
• TupleToEncodedIter
  Trait to indicate that a tuple can be converted into an iterator of a vector of encoded bytes.