pub struct StorageMap<Prefix, Hasher, Key, Value, QueryKind = OptionQuery, OnEmpty = GetDefault, MaxValues = GetDefault>(/* private fields */);
Expand description

A type representing a map in storage. A storage map is a mapping of keys to values of a given type stored on-chain.

For general information regarding the #[pallet::storage] attribute, refer to crate::pallet_macros::storage.

Example

#[frame_support::pallet]
mod pallet {
	/// A kitchen-sink StorageMap, with all possible additional attributes.
    #[pallet::storage]
	#[pallet::getter(fn foo)]
	#[pallet::storage_prefix = "OtherFoo"]
	#[pallet::unbounded]
    pub type Foo<T> = StorageMap<
		_,
		Blake2_128Concat,
		u32,
		u32,
		ValueQuery
	>;

	/// Alternative named syntax.
    #[pallet::storage]
    pub type Bar<T> = StorageMap<
		Hasher = Blake2_128Concat,
		Key = u32,
		Value = u32,
		QueryKind = ValueQuery
	>;
}

Implementations§

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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Prefix: StorageInstance, Hasher: StorageHasher, Key: FullCodec, Value: FullCodec, QueryKind: QueryKindTrait<Value, OnEmpty>, OnEmpty: Get<QueryKind::Query> + 'static, MaxValues: Get<Option<u32>>,

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pub fn hashed_key_for<KeyArg: EncodeLike<Key>>(key: KeyArg) -> Vec<u8>

Get the storage key used to fetch a value corresponding to a specific key.

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pub fn contains_key<KeyArg: EncodeLike<Key>>(key: KeyArg) -> bool

Does the value (explicitly) exist in storage?

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pub fn get<KeyArg: EncodeLike<Key>>(key: KeyArg) -> QueryKind::Query

Load the value associated with the given key from the map.

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pub fn try_get<KeyArg: EncodeLike<Key>>(key: KeyArg) -> Result<Value, ()>

Try to get the value for the given key from the map.

Returns Ok if it exists, Err if not.

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pub fn swap<KeyArg1: EncodeLike<Key>, KeyArg2: EncodeLike<Key>>( key1: KeyArg1, key2: KeyArg2 )

Swap the values of two keys.

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pub fn set<KeyArg: EncodeLike<Key>>(key: KeyArg, q: QueryKind::Query)

Store or remove the value to be associated with key so that get returns the query.

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pub fn insert<KeyArg: EncodeLike<Key>, ValArg: EncodeLike<Value>>( key: KeyArg, val: ValArg )

Store a value to be associated with the given key from the map.

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pub fn remove<KeyArg: EncodeLike<Key>>(key: KeyArg)

Remove the value under a key.

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pub fn mutate<KeyArg: EncodeLike<Key>, R, F: FnOnce(&mut QueryKind::Query) -> R>( key: KeyArg, f: F ) -> R

Mutate the value under a key.

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pub fn try_mutate<KeyArg, R, E, F>(key: KeyArg, f: F) -> Result<R, E>where KeyArg: EncodeLike<Key>, F: FnOnce(&mut QueryKind::Query) -> Result<R, E>,

Mutate the item, only if an Ok value is returned.

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pub fn mutate_extant<KeyArg: EncodeLike<Key>, R: Default, F: FnOnce(&mut Value) -> R>( key: KeyArg, f: F ) -> R

Mutate the value under a key iff it exists. Do nothing and return the default value if not.

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pub fn mutate_exists<KeyArg: EncodeLike<Key>, R, F: FnOnce(&mut Option<Value>) -> R>( key: KeyArg, f: F ) -> R

Mutate the value under a key. Deletes the item if mutated to a None.

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pub fn try_mutate_exists<KeyArg, R, E, F>(key: KeyArg, f: F) -> Result<R, E>where KeyArg: EncodeLike<Key>, F: FnOnce(&mut Option<Value>) -> Result<R, E>,

Mutate the item, only if an Ok value is returned. Deletes the item if mutated to a None. f will always be called with an option representing if the storage item exists (Some<V>) or if the storage item does not exist (None), independent of the QueryType.

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pub fn take<KeyArg: EncodeLike<Key>>(key: KeyArg) -> QueryKind::Query

Take the value under a key.

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pub fn append<Item, EncodeLikeItem, EncodeLikeKey>( key: EncodeLikeKey, item: EncodeLikeItem )where EncodeLikeKey: EncodeLike<Key>, Item: Encode, EncodeLikeItem: EncodeLike<Item>, Value: StorageAppend<Item>,

Append the given items to the value in the storage.

Value is required to implement codec::EncodeAppend.

Warning

If the storage item is not encoded properly, the storage will be overwritten and set to [item]. Any default value set for the storage item will be ignored on overwrite.

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pub fn decode_len<KeyArg: EncodeLike<Key>>(key: KeyArg) -> Option<usize>where Value: StorageDecodeLength,

Read the length of the storage value without decoding the entire value under the given key.

Value is required to implement StorageDecodeLength.

If the value does not exists or it fails to decode the length, None is returned. Otherwise Some(len) is returned.

Warning

None does not mean that get() does not return a value. The default value is completly ignored by this function.

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pub fn decode_non_dedup_len<KeyArg: EncodeLike<Key>>( key: KeyArg ) -> Option<usize>where Value: StorageDecodeNonDedupLength,

Read the length of the storage value without decoding the entire value.

Value is required to implement StorageDecodeNonDedupLength.

If the value does not exists or it fails to decode the length, None is returned. Otherwise Some(len) is returned.

Warning
  • None does not mean that get() does not return a value. The default value is completly ignored by this function.

  • The value returned is the non-deduplicated length of the underlying Vector in storage.This means that any duplicate items are included.

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pub fn migrate_key<OldHasher: StorageHasher, KeyArg: EncodeLike<Key>>( key: KeyArg ) -> Option<Value>

Migrate an item with the given key from a defunct OldHasher to the current hasher.

If the key doesn’t exist, then it’s a no-op. If it does, then it returns its value.

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pub fn remove_all(limit: Option<u32>) -> KillStorageResult

👎Deprecated: Use clear instead

Remove all values of the storage in the overlay and up to limit in the backend.

All values in the client overlay will be deleted, if there is some limit then up to limit values are deleted from the client backend, if limit is none then all values in the client backend are deleted.

Note

Calling this multiple times per block with a limit set leads always to the same keys being removed and the same result being returned. This happens because the keys to delete in the overlay are not taken into account when deleting keys in the backend.

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pub fn clear(limit: u32, maybe_cursor: Option<&[u8]>) -> MultiRemovalResults

Attempt to remove all items from the map.

Returns MultiRemovalResults to inform about the result. Once the resultant maybe_cursor field is None, then no further items remain to be deleted.

NOTE: After the initial call for any given map, it is important that no further items are inserted into the map. If so, then the map may not be empty when the resultant maybe_cursor is None.

Limit

A limit must always be provided through in order to cap the maximum amount of deletions done in a single call. This is one fewer than the maximum number of backend iterations which may be done by this operation and as such represents the maximum number of backend deletions which may happen. A limit of zero implies that no keys will be deleted, though there may be a single iteration done.

Cursor

A cursor may be passed in to this operation with maybe_cursor. None should only be passed once (in the initial call) for any given storage map. Subsequent calls operating on the same map should always pass Some, and this should be equal to the previous call result’s maybe_cursor field.

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pub fn iter_values() -> PrefixIterator<Value>

Iter over all value of the storage.

NOTE: If a value failed to decode because storage is corrupted then it is skipped.

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pub fn translate_values<OldValue: Decode, F: FnMut(OldValue) -> Option<Value>>( f: F )

Translate the values of all elements by a function f, in the map in no particular order.

By returning None from f for an element, you’ll remove it from the map.

NOTE: If a value fail to decode because storage is corrupted then it is skipped.

Warning

This function must be used with care, before being updated the storage still contains the old type, thus other calls (such as get) will fail at decoding it.

Usage

This would typically be called inside the module implementation of on_runtime_upgrade.

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pub fn try_append<KArg, Item, EncodeLikeItem>( key: KArg, item: EncodeLikeItem ) -> Result<(), ()>where KArg: EncodeLike<Key> + Clone, Item: Encode, EncodeLikeItem: EncodeLike<Item>, Value: StorageTryAppend<Item>,

Try and append the given item to the value in the storage.

Is only available if Value of the storage implements StorageTryAppend.

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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Prefix: StorageInstance, Hasher: StorageHasher + ReversibleStorageHasher, Key: FullCodec, Value: FullCodec, QueryKind: QueryKindTrait<Value, OnEmpty>, OnEmpty: Get<QueryKind::Query> + 'static, MaxValues: Get<Option<u32>>,

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pub fn iter() -> PrefixIterator<(Key, Value)>

Enumerate all elements in the map in no particular order.

If you alter the map while doing this, you’ll get undefined results.

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pub fn iter_from(starting_raw_key: Vec<u8>) -> PrefixIterator<(Key, Value)>

Enumerate all elements in the map after a specified starting_raw_key in no particular order.

If you alter the map while doing this, you’ll get undefined results.

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pub fn iter_from_key( starting_key: impl EncodeLike<Key> ) -> PrefixIterator<(Key, Value)>

Enumerate all elements in the map after a specified starting_key in no particular order.

If you alter the map while doing this, you’ll get undefined results.

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pub fn iter_keys() -> KeyPrefixIterator<Key>

Enumerate all keys in the map in no particular order.

If you alter the map while doing this, you’ll get undefined results.

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pub fn iter_keys_from(starting_raw_key: Vec<u8>) -> KeyPrefixIterator<Key>

Enumerate all keys in the map after a specified starting_raw_key in no particular order.

If you alter the map while doing this, you’ll get undefined results.

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pub fn iter_keys_from_key( starting_key: impl EncodeLike<Key> ) -> KeyPrefixIterator<Key>

Enumerate all keys in the map after a specified starting_key in no particular order.

If you alter the map while doing this, you’ll get undefined results.

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pub fn drain() -> PrefixIterator<(Key, Value)>

Remove all elements from the map and iterate through them in no particular order.

If you add elements to the map while doing this, you’ll get undefined results.

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pub fn translate<O: Decode, F: FnMut(Key, O) -> Option<Value>>(f: F)

Translate the values of all elements by a function f, in the map in no particular order.

By returning None from f for an element, you’ll remove it from the map.

NOTE: If a value fails to decode because storage is corrupted, then it will log an error and be skipped in production, or panic in development.

Trait Implementations§

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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> PartialStorageInfoTrait for StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Prefix: StorageInstance, Hasher: StorageHasher, Key: FullCodec, Value: FullCodec, QueryKind: QueryKindTrait<Value, OnEmpty>, OnEmpty: Get<QueryKind::Query> + 'static, MaxValues: Get<Option<u32>>,

It doesn’t require to implement MaxEncodedLen and give no information for max_size.

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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> StorageEntryMetadataBuilder for StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Prefix: StorageInstance, Hasher: StorageHasher, Key: FullCodec + StaticTypeInfo, Value: FullCodec + StaticTypeInfo, QueryKind: QueryKindTrait<Value, OnEmpty>, OnEmpty: Get<QueryKind::Query> + 'static, MaxValues: Get<Option<u32>>,

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fn build_metadata( docs: Vec<&'static str>, entries: &mut Vec<StorageEntryMetadataIR> )

Build into entries the storage metadata entries of a storage given some docs.
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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> StorageInfoTrait for StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Prefix: StorageInstance, Hasher: StorageHasher, Key: FullCodec + MaxEncodedLen, Value: FullCodec + MaxEncodedLen, QueryKind: QueryKindTrait<Value, OnEmpty>, OnEmpty: Get<QueryKind::Query> + 'static, MaxValues: Get<Option<u32>>,

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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> StoragePrefixedMap<Value> for StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Prefix: StorageInstance, Hasher: StorageHasher, Key: FullCodec, Value: FullCodec, QueryKind: QueryKindTrait<Value, OnEmpty>, OnEmpty: Get<QueryKind::Query> + 'static, MaxValues: Get<Option<u32>>,

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fn pallet_prefix() -> &'static [u8]

Pallet prefix. Used for generating final key.
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fn storage_prefix() -> &'static [u8]

Storage prefix. Used for generating final key.
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fn final_prefix() -> [u8; 32]

Final full prefix that prefixes all keys.
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fn remove_all(limit: Option<u32>) -> KillStorageResult

👎Deprecated: Use clear instead
Remove all values in the overlay and up to limit in the backend. Read more
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fn clear(limit: u32, maybe_cursor: Option<&[u8]>) -> MultiRemovalResults

Attempt to remove all items from the map. Read more
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fn iter_values() -> PrefixIterator<Value>

Iter over all value of the storage. Read more
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fn translate_values<OldValue: Decode, F: FnMut(OldValue) -> Option<Value>>(f: F)

Translate the values of all elements by a function f, in the map in no particular order. By returning None from f for an element, you’ll remove it from the map. Read more
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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> TryDecodeEntireStorage for StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Prefix: StorageInstance, Hasher: StorageHasher, Key: FullCodec, Value: FullCodec, QueryKind: QueryKindTrait<Value, OnEmpty>, OnEmpty: Get<QueryKind::Query> + 'static, MaxValues: Get<Option<u32>>,

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fn try_decode_entire_state() -> Result<usize, Vec<TryDecodeEntireStorageError>>

Decode the entire data under the given storage, returning Ok(bytes_decoded) if success.

Auto Trait Implementations§

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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> RefUnwindSafe for StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Hasher: RefUnwindSafe, Key: RefUnwindSafe, MaxValues: RefUnwindSafe, OnEmpty: RefUnwindSafe, Prefix: RefUnwindSafe, QueryKind: RefUnwindSafe, Value: RefUnwindSafe,

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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> Send for StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Hasher: Send, Key: Send, MaxValues: Send, OnEmpty: Send, Prefix: Send, QueryKind: Send, Value: Send,

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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> Sync for StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Hasher: Sync, Key: Sync, MaxValues: Sync, OnEmpty: Sync, Prefix: Sync, QueryKind: Sync, Value: Sync,

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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> Unpin for StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Hasher: Unpin, Key: Unpin, MaxValues: Unpin, OnEmpty: Unpin, Prefix: Unpin, QueryKind: Unpin, Value: Unpin,

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impl<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues> UnwindSafe for StorageMap<Prefix, Hasher, Key, Value, QueryKind, OnEmpty, MaxValues>where Hasher: UnwindSafe, Key: UnwindSafe, MaxValues: UnwindSafe, OnEmpty: UnwindSafe, Prefix: UnwindSafe, QueryKind: UnwindSafe, Value: UnwindSafe,

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impl<T> Any for Twhere T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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Immutably borrows from an owned value. Read more
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Mutably borrows from an owned value. Read more
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impl<T> CheckedConversion for T

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fn checked_from<T>(t: T) -> Option<Self>where Self: TryFrom<T>,

Convert from a value of T into an equivalent instance of Option<Self>. Read more
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Consume self to return Some equivalent value of Option<T>. Read more
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impl<T> Conv for T

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fn conv<T>(self) -> Twhere Self: Into<T>,

Converts self into T using Into<T>. Read more
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fn fmt_binary(self) -> FmtBinary<Self>where Self: Binary,

Causes self to use its Binary implementation when Debug-formatted.
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fn fmt_lower_exp(self) -> FmtLowerExp<Self>where Self: LowerExp,

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Causes self to use its LowerHex implementation when Debug-formatted.
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Formats each item in a sequence. Read more
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fn from(t: T) -> T

Returns the argument unchanged.

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fn instrument(self, span: Span) -> Instrumented<Self>

Instruments this type with the provided Span, returning an Instrumented wrapper. Read more
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Instruments this type with the current Span, returning an Instrumented wrapper. Read more
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impl<T, U> Into<U> for Twhere U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T, U> IntoKey<U> for Twhere U: FromKey<T>,

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fn into_key(self) -> U

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impl<T> IsType<T> for T

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fn from_ref(t: &T) -> &T

Cast reference.
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fn into_ref(&self) -> &T

Cast reference.
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Cast mutable reference.
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Cast mutable reference.
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fn from_ref(outer: &Outer) -> &T

Get a reference to the inner from the outer.

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Get a mutable reference to the inner from the outer.

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fn pipe<R>(self, func: impl FnOnce(Self) -> R) -> Rwhere Self: Sized,

Pipes by value. This is generally the method you want to use. Read more
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fn pipe_ref<'a, R>(&'a self, func: impl FnOnce(&'a Self) -> R) -> Rwhere R: 'a,

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const ALIGN: usize = _

The alignment of pointer.
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type Init = T

The type for initializers.
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unsafe fn init(init: <T as Pointable>::Init) -> usize

Initializes a with the given initializer. Read more
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unsafe fn deref<'a>(ptr: usize) -> &'a T

Dereferences the given pointer. Read more
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unsafe fn drop(ptr: usize)

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type Output = T

Should always be Self
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fn saturated_into<T>(self) -> Twhere Self: UniqueSaturatedInto<T>,

Consume self to return an equivalent value of T. Read more
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impl<K, V, G> StorageMap<K, V> for Gwhere K: FullEncode, V: FullCodec, G: StorageMap<K, V>,

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type Query = <G as StorageMap<K, V>>::Query

The type that get/take return.
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fn hashed_key_for<KeyArg>(key: KeyArg) -> Vec<u8> where KeyArg: EncodeLike<K>,

Get the storage key used to fetch a value corresponding to a specific key.
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fn swap<KeyArg1, KeyArg2>(key1: KeyArg1, key2: KeyArg2)where KeyArg1: EncodeLike<K>, KeyArg2: EncodeLike<K>,

Swap the values of two keys.
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fn contains_key<KeyArg>(key: KeyArg) -> boolwhere KeyArg: EncodeLike<K>,

Does the value (explicitly) exist in storage?
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fn get<KeyArg>(key: KeyArg) -> <G as StorageMap<K, V>>::Querywhere KeyArg: EncodeLike<K>,

Load the value associated with the given key from the map.
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fn try_get<KeyArg>(key: KeyArg) -> Result<V, ()>where KeyArg: EncodeLike<K>,

Try to get the value for the given key from the map. Read more
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fn set<KeyArg>(key: KeyArg, q: <G as StorageMap<K, V>>::Query)where KeyArg: EncodeLike<K>,

Store or remove the value to be associated with key so that get returns the query.
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fn insert<KeyArg, ValArg>(key: KeyArg, val: ValArg)where KeyArg: EncodeLike<K>, ValArg: EncodeLike<V>,

Store a value to be associated with the given key from the map.
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fn remove<KeyArg>(key: KeyArg)where KeyArg: EncodeLike<K>,

Remove the value under a key.
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fn mutate<KeyArg, R, F>(key: KeyArg, f: F) -> Rwhere KeyArg: EncodeLike<K>, F: FnOnce(&mut <G as StorageMap<K, V>>::Query) -> R,

Mutate the value under a key.
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fn mutate_exists<KeyArg, R, F>(key: KeyArg, f: F) -> Rwhere KeyArg: EncodeLike<K>, F: FnOnce(&mut Option<V>) -> R,

Mutate the value under a key. Read more
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fn try_mutate<KeyArg, R, E, F>(key: KeyArg, f: F) -> Result<R, E>where KeyArg: EncodeLike<K>, F: FnOnce(&mut <G as StorageMap<K, V>>::Query) -> Result<R, E>,

Mutate the item, only if an Ok value is returned.
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fn try_mutate_exists<KeyArg, R, E, F>(key: KeyArg, f: F) -> Result<R, E>where KeyArg: EncodeLike<K>, F: FnOnce(&mut Option<V>) -> Result<R, E>,

Mutate the item, only if an Ok value is returned. Deletes the item if mutated to a None. f will always be called with an option representing if the storage item exists (Some<V>) or if the storage item does not exist (None), independent of the QueryType.
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fn take<KeyArg>(key: KeyArg) -> <G as StorageMap<K, V>>::Querywhere KeyArg: EncodeLike<K>,

Take the value under a key.
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fn append<Item, EncodeLikeItem, EncodeLikeKey>( key: EncodeLikeKey, item: EncodeLikeItem )where EncodeLikeKey: EncodeLike<K>, Item: Encode, EncodeLikeItem: EncodeLike<Item>, V: StorageAppend<Item>,

Append the given items to the value in the storage. Read more
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fn migrate_key<OldHasher, KeyArg>(key: KeyArg) -> Option<V>where OldHasher: StorageHasher, KeyArg: EncodeLike<K>,

Migrate an item with the given key from a defunct OldHasher to the current hasher. Read more
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fn mutate_extant<KeyArg: EncodeLike<K>, R: Default, F: FnOnce(&mut V) -> R>( key: KeyArg, f: F ) -> R

Mutate the value under a key if the value already exists. Do nothing and return the default value if not.
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fn decode_len<KeyArg: EncodeLike<K>>(key: KeyArg) -> Option<usize>where V: StorageDecodeLength,

Read the length of the storage value without decoding the entire value under the given key. Read more
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fn decode_non_dedup_len<KeyArg: EncodeLike<K>>(key: KeyArg) -> Option<usize>where V: StorageDecodeNonDedupLength,

Read the length of the storage value without decoding the entire value. Read more
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fn migrate_key_from_blake<KeyArg: EncodeLike<K>>(key: KeyArg) -> Option<V>

Migrate an item with the given key from a blake2_256 hasher to the current hasher. Read more
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impl<T> Tap for T

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fn tap(self, func: impl FnOnce(&Self)) -> Self

Immutable access to a value. Read more
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fn tap_mut(self, func: impl FnOnce(&mut Self)) -> Self

Mutable access to a value. Read more
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fn tap_borrow<B>(self, func: impl FnOnce(&B)) -> Selfwhere Self: Borrow<B>, B: ?Sized,

Immutable access to the Borrow<B> of a value. Read more
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fn tap_borrow_mut<B>(self, func: impl FnOnce(&mut B)) -> Selfwhere Self: BorrowMut<B>, B: ?Sized,

Mutable access to the BorrowMut<B> of a value. Read more
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fn tap_ref<R>(self, func: impl FnOnce(&R)) -> Selfwhere Self: AsRef<R>, R: ?Sized,

Immutable access to the AsRef<R> view of a value. Read more
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fn tap_ref_mut<R>(self, func: impl FnOnce(&mut R)) -> Selfwhere Self: AsMut<R>, R: ?Sized,

Mutable access to the AsMut<R> view of a value. Read more
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fn tap_deref<T>(self, func: impl FnOnce(&T)) -> Selfwhere Self: Deref<Target = T>, T: ?Sized,

Immutable access to the Deref::Target of a value. Read more
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fn tap_deref_mut<T>(self, func: impl FnOnce(&mut T)) -> Selfwhere Self: DerefMut<Target = T> + Deref, T: ?Sized,

Mutable access to the Deref::Target of a value. Read more
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fn tap_dbg(self, func: impl FnOnce(&Self)) -> Self

Calls .tap() only in debug builds, and is erased in release builds.
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fn tap_mut_dbg(self, func: impl FnOnce(&mut Self)) -> Self

Calls .tap_mut() only in debug builds, and is erased in release builds.
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fn tap_borrow_dbg<B>(self, func: impl FnOnce(&B)) -> Selfwhere Self: Borrow<B>, B: ?Sized,

Calls .tap_borrow() only in debug builds, and is erased in release builds.
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fn tap_borrow_mut_dbg<B>(self, func: impl FnOnce(&mut B)) -> Selfwhere Self: BorrowMut<B>, B: ?Sized,

Calls .tap_borrow_mut() only in debug builds, and is erased in release builds.
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fn tap_ref_dbg<R>(self, func: impl FnOnce(&R)) -> Selfwhere Self: AsRef<R>, R: ?Sized,

Calls .tap_ref() only in debug builds, and is erased in release builds.
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fn tap_ref_mut_dbg<R>(self, func: impl FnOnce(&mut R)) -> Selfwhere Self: AsMut<R>, R: ?Sized,

Calls .tap_ref_mut() only in debug builds, and is erased in release builds.
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fn tap_deref_dbg<T>(self, func: impl FnOnce(&T)) -> Selfwhere Self: Deref<Target = T>, T: ?Sized,

Calls .tap_deref() only in debug builds, and is erased in release builds.
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fn tap_deref_mut_dbg<T>(self, func: impl FnOnce(&mut T)) -> Selfwhere Self: DerefMut<Target = T> + Deref, T: ?Sized,

Calls .tap_deref_mut() only in debug builds, and is erased in release builds.
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impl<K, T, I, StorageMapT> TryAppendMap<K, T, I> for StorageMapTwhere K: FullCodec, T: FullCodec + StorageTryAppend<I>, I: Encode, StorageMapT: StorageMap<K, T>,

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fn try_append<LikeK, LikeI>(key: LikeK, item: LikeI) -> Result<(), ()>where LikeK: EncodeLike<K> + Clone, LikeI: EncodeLike<I>,

Try and append the item into the storage map at the given key. Read more
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impl<T> TryConv for T

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fn try_conv<T>(self) -> Result<T, Self::Error>where Self: TryInto<T>,

Attempts to convert self into T using TryInto<T>. Read more
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impl<T, U> TryFrom<U> for Twhere U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for Twhere U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
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impl<T, U> TryIntoKey<U> for Twhere U: TryFromKey<T>,

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type Error = <U as TryFromKey<T>>::Error

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fn try_into_key(self) -> Result<U, <U as TryFromKey<T>>::Error>

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impl<S, T> UncheckedInto<T> for Swhere T: UncheckedFrom<S>,

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fn unchecked_into(self) -> T

The counterpart to unchecked_from.
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impl<T, S> UniqueSaturatedInto<T> for Swhere T: Bounded, S: TryInto<T>,

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fn unique_saturated_into(self) -> T

Consume self to return an equivalent value of T.
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impl<V, T> VZip<V> for Twhere V: MultiLane<T>,

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fn vzip(self) -> V

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impl<T> WithSubscriber for T

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fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>where S: Into<Dispatch>,

Attaches the provided Subscriber to this type, returning a WithDispatch wrapper. Read more
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fn with_current_subscriber(self) -> WithDispatch<Self>

Attaches the current default Subscriber to this type, returning a WithDispatch wrapper. Read more
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impl<T> JsonSchemaMaybe for T

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impl<T> MaybeRefUnwindSafe for Twhere T: RefUnwindSafe,

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impl<T> MaybeRefUnwindSafe for Twhere T: RefUnwindSafe,