pub enum DigestItem<Hash> {
    ChangesTrieRoot(Hash),
    PreRuntime(ConsensusEngineIdVec<u8>),
    Consensus(ConsensusEngineIdVec<u8>),
    Seal(ConsensusEngineIdVec<u8>),
    ChangesTrieSignal(ChangesTrieSignal),
    Other(Vec<u8>),
}
Expand description

Digest item that is able to encode/decode ‘system’ digest items and provide opaque access to other items.

Variants

ChangesTrieRoot(Hash)

System digest item that contains the root of changes trie at given block. It is created for every block iff runtime supports changes trie creation.

PreRuntime(ConsensusEngineIdVec<u8>)

A pre-runtime digest.

These are messages from the consensus engine to the runtime, although the consensus engine can (and should) read them itself to avoid code and state duplication. It is erroneous for a runtime to produce these, but this is not (yet) checked.

NOTE: the runtime is not allowed to panic or fail in an on_initialize call if an expected PreRuntime digest is not present. It is the responsibility of a external block verifier to check this. Runtime API calls will initialize the block without pre-runtime digests, so initialization cannot fail when they are missing.

Consensus(ConsensusEngineIdVec<u8>)

A message from the runtime to the consensus engine. This should never be generated by the native code of any consensus engine, but this is not checked (yet).

Seal(ConsensusEngineIdVec<u8>)

Put a Seal on it. This is only used by native code, and is never seen by runtimes.

ChangesTrieSignal(ChangesTrieSignal)

Digest item that contains signal from changes tries manager to the native code.

Other(Vec<u8>)

Some other thing. Unsupported and experimental.

Implementations

Returns a ‘referencing view’ for this digest item.

Returns Some if the entry is the ChangesTrieRoot entry.

Returns Some if this entry is the PreRuntime entry.

Returns Some if this entry is the Consensus entry.

Returns Some if this entry is the Seal entry.

Returns Some if the entry is the ChangesTrieSignal entry.

Returns Some if self is a DigestItem::Other.

Returns the opaque data contained in the item if Some if this entry has the id given.

Returns the data contained in the item if Some if this entry has the id given, decoded to the type provided T.

Trait Implementations

Perform the equality check.

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Attempt to deserialise the value from input.

Attempt to skip the encoded value from input. Read more

Returns the fixed encoded size of the type. Read more

Deserialize this value from the given Serde deserializer. Read more

Convert self to an owned vector.

If possible give a hint of expected size of the encoding. Read more

Convert self to a slice and append it to the destination.

Convert self to a slice and then invoke the given closure with it.

Calculates the encoded size. Read more

Measure the heap usage of all descendant heap-allocated structures, but not the space taken up by the value itself. If T::size_of is a constant, consider implementing constant_size as well. Read more

Used to optimize MallocSizeOf implementation for collections like Vec and HashMap to avoid iterating over them unnecessarily. The Self: Sized bound is for object safety. Read more

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

Serialize this value into the given Serde serializer. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

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

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

Decode Self and consume all of the given input data. Read more

Decode Self and consume all of the given input data. Read more

Decode Self with the given maximum recursion depth. Read more

Returns the argument unchanged.

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

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

Calls U::from(self).

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

Get a reference to the inner from the outer.

Get a mutable reference to the inner from the outer.

Return an encoding of Self prepended by given slice.

Method to launch a heapsize measurement with a fresh state. Read more

Should always be Self

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

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

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

🔬 This is a nightly-only experimental API. (toowned_clone_into)

Uses borrowed data to replace owned data, usually by cloning. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.

The counterpart to unchecked_from.

Consume self to return an equivalent value of T.