Trait CountedByKey 

pub trait CountedByKey {
    type Key;
    type Length: Default + PartialEq;

    // Required method
    fn len(key: &Self::Key) -> Self::Length;

    // Provided method
    fn is_empty(key: &Self::Key) -> bool { ... }
}

Represents default counting logic, by providing ability to return length of the object as specified (associated) type or answer the question is the object empty, by provided key of specified (associated) type.

Should be implemented on double map based types.

Required Associated Types

type Key

Key type of counting target.

type Length: Default + PartialEq

Returning length type.

Required Methods

fn len(key: &Self::Key) -> Self::Length

Returns current Self’s amount of elements as Length type.

Provided Methods

fn is_empty(key: &Self::Key) -> bool

Returns bool, defining if Self doesn’t contain elements.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<T, Task, Error, OutputError, Callbacks> CountedByKey for TaskPoolImpl<T, Task, Error, OutputError, Callbacks>

where T: DoubleMapStorage<Key2 = Task, Value = ()> + CountedByKey<Key = T::Key1>, Error: TaskPoolError, OutputError: From<Error>, Callbacks: TaskPoolCallbacks,

type Key = <T as DoubleMapStorage>::Key1

type Length = <T as CountedByKey>::Length

impl<T, Value, BlockNumber, Error, OutputError, Callbacks, KeyGen> CountedByKey for MailboxImpl<T, Value, BlockNumber, Error, OutputError, Callbacks, KeyGen>

where T: DoubleMapStorage<Value = (Value, Interval<BlockNumber>)> + CountedByKey<Key = T::Key1>, Error: MailboxError, OutputError: From<Error>, Callbacks: MailboxCallbacks<OutputError, Value = Value, BlockNumber = BlockNumber>, KeyGen: KeyFor<Key = (T::Key1, T::Key2), Value = Value>,

type Key = <T as DoubleMapStorage>::Key1

type Length = <T as CountedByKey>::Length

impl<T, Value, BlockNumber, Error, OutputError, Callbacks, KeyGen> CountedByKey for WaitlistImpl<T, Value, BlockNumber, Error, OutputError, Callbacks, KeyGen>

where T: DoubleMapStorage<Value = (Value, Interval<BlockNumber>)> + CountedByKey<Key = T::Key1>, Error: WaitlistError, OutputError: From<Error>, Callbacks: WaitlistCallbacks<Value = Value, BlockNumber = BlockNumber>, KeyGen: KeyFor<Key = (T::Key1, T::Key2), Value = Value>,

type Key = <T as DoubleMapStorage>::Key1

type Length = <T as CountedByKey>::Length

impl<T: AuxiliaryDoubleStorageWrap> CountedByKey for T

Available on crate feature std only.

type Key = <T as AuxiliaryDoubleStorageWrap>::Key1

type Length = usize