Struct frame_support::storage::types::Key

pub struct Key<Hasher, KeyType>(/* private fields */);

Expand description

A type used exclusively by storage maps as their key type.

The final key generated has the following form:

Hasher1(encode(key1))
    ++ Hasher2(encode(key2))
    ++ ...
    ++ HasherN(encode(keyN))

Trait Implementations§

impl<H: StorageHasher, K: FullCodec + StaticTypeInfo> KeyGenerator for Key<H, K>

type Key = K

type KArg = (K,)

type HashFn = Box<dyn FnOnce(&[u8]) -> Vec<u8>>

type HArg = (<Key<H, K> as KeyGenerator>::HashFn,)

const HASHER_METADATA: &'static [StorageHasherIR] = _

fn final_key<KArg: EncodeLikeTuple<Self::KArg> + TupleToEncodedIter>( key: KArg ) -> Vec<u8> ⓘ

Given a key tuple, calculate the final key by encoding each element individually and hashing them using the corresponding hasher in the KeyGenerator.

fn migrate_key<KArg: EncodeLikeTuple<Self::KArg> + TupleToEncodedIter>( key: &KArg, hash_fns: Self::HArg ) -> Vec<u8> ⓘ

Given a key tuple, migrate the keys from using the old hashers as given by hash_fns to using the newer hashers as specified by this KeyGenerator.

impl<H: StorageHasher, K: FullCodec + MaxEncodedLen + StaticTypeInfo> KeyGeneratorMaxEncodedLen for Key<H, K>

fn key_max_encoded_len() -> usize

impl<H: ReversibleStorageHasher, K: FullCodec + StaticTypeInfo> ReversibleKeyGenerator for Key<H, K>

type ReversibleHasher = H

fn decode_final_key(key_material: &[u8]) -> Result<(Self::Key, &[u8]), Error>

Auto Trait Implementations§

impl<Hasher, KeyType> RefUnwindSafe for Key<Hasher, KeyType>
where Hasher: RefUnwindSafe, KeyType: RefUnwindSafe,

impl<Hasher, KeyType> Send for Key<Hasher, KeyType>
where Hasher: Send, KeyType: Send,

impl<Hasher, KeyType> Sync for Key<Hasher, KeyType>
where Hasher: Sync, KeyType: Sync,

impl<Hasher, KeyType> Unpin for Key<Hasher, KeyType>
where Hasher: Unpin, KeyType: Unpin,

impl<Hasher, KeyType> UnwindSafe for Key<Hasher, KeyType>
where Hasher: UnwindSafe, KeyType: UnwindSafe,

Blanket Implementations§

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

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more

impl<T> Borrow<T> for T
where T: ?Sized,

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more

impl<T> BorrowMut<T> for T
where T: ?Sized,

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more

impl<T> CheckedConversion for T

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

fn checked_into<T>(self) -> Option<T>
where Self: TryInto<T>,

Consume self to return Some equivalent value of Option<T>. Read more

impl<T> From<T> for T

fn from(t: T) -> T

Returns the argument unchanged.

impl<T> Instrument for T

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

Instruments this type with the provided [Span], returning an Instrumented wrapper. Read more

fn in_current_span(self) -> Instrumented<Self>

Instruments this type with the current Span, returning an Instrumented wrapper. Read more

impl<T, U> Into<U> for T
where U: From<T>,

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Calls U::from(self).

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

impl<T> IsType<T> for T

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

Cast reference.

fn into_ref(&self) -> &T

Cast reference.

fn from_mut(t: &mut T) -> &mut T

Cast mutable reference.

fn into_mut(&mut self) -> &mut T

Cast mutable reference.

impl<T, Outer> IsWrappedBy<Outer> for T
where Outer: AsRef<T> + AsMut<T> + From<T>, T: From<Outer>,

fn from_ref(outer: &Outer) -> &T

Get a reference to the inner from the outer.

fn from_mut(outer: &mut Outer) -> &mut T

Get a mutable reference to the inner from the outer.

impl<T> Same for T

type Output = T

Should always be Self

impl<T> SaturatedConversion for T

fn saturated_from<T>(t: T) -> Self
where Self: UniqueSaturatedFrom<T>,

Convert from a value of T into an equivalent instance of Self. Read more

fn saturated_into<T>(self) -> T
where Self: UniqueSaturatedInto<T>,

Consume self to return an equivalent value of T. Read more

impl<T, U> TryFrom<U> for T
where U: Into<T>,

type Error = Infallible

The type returned in the event of a conversion error.

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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

The type returned in the event of a conversion error.

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.

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

fn unchecked_into(self) -> T

The counterpart to unchecked_from.

impl<T, S> UniqueSaturatedInto<T> for S
where T: Bounded, S: TryInto<T>,

fn unique_saturated_into(self) -> T

Consume self to return an equivalent value of T.

impl<V, T> VZip<V> for T
where V: MultiLane<T>,

fn vzip(self) -> V

impl<T> WithSubscriber for T

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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Attaches the current default Subscriber to this type, returning a [WithDispatch] wrapper. Read more

impl<T> JsonSchemaMaybe for T

impl<T> MaybeRefUnwindSafe for T
where T: RefUnwindSafe,