Enum RevealableSparseTrie 

pub enum RevealableSparseTrie<T = ArenaParallelSparseTrie> {
    Blind(Option<Box<T>>),
    Revealed(Box<T>),
}

A sparse trie that is either in a “blind” state (no nodes are revealed, root node hash is unknown) or in a “revealed” state (root node has been revealed and the trie can be updated).

In blind mode the trie does not contain any decoded node data, which saves memory but prevents direct access to node contents. The revealed mode stores decoded nodes along with additional information such as values, allowing direct manipulation.

The sparse trie design is optimised for:

1. Memory efficiency - only revealed nodes are loaded into memory
2. Update tracking - changes to the trie structure can be tracked and selectively persisted
3. Incremental operations - nodes can be revealed as needed without loading the entire trie. This is what gives rise to the notion of a “sparse” trie.

Variants

Blind(Option<Box<T>>)

The trie is blind – no nodes have been revealed

This is the default state. In this state, the trie cannot be directly queried or modified until nodes are revealed.

In this state the RevealableSparseTrie can optionally carry with it a cleared sparse trie. This allows for reusing the trie’s allocations between payload executions.

Revealed(Box<T>)

Some nodes in the Trie have been revealed.

In this state, the trie can be queried and modified for the parts that have been revealed. Other parts remain blind and require revealing before they can be accessed.

Implementations

impl<T: SparseTrieTrait + Default> RevealableSparseTrie<T>

pub fn revealed_empty() -> Self

Creates a new revealed but empty sparse trie.

pub fn reveal_root( &mut self, root: TrieNodeV2, masks: Option<BranchNodeMasks>, retain_updates: bool, ) -> SparseTrieResult<&mut T>

Reveals the root node, converting a blind trie into a revealed one.

If the trie is blinded, its root node is replaced with root.

The masks are used to determine how the node’s children are stored. The retention flag controls whether trie updates should be tracked.

Returns

A mutable reference to the underlying RevealableSparseTrie.

pub fn reveal_v2_proof_nodes( &mut self, nodes: &mut [ProofTrieNodeV2], retain_updates: bool, ) -> SparseTrieResult<()>

Reveals a batch of V2 proof nodes into this trie.

If nodes contains a node at the empty path it is used to reveal the root (transitioning the trie from blind to revealed). Otherwise the trie must already be revealed.

impl<T: SparseTrieTrait> RevealableSparseTrie<T>

pub const fn blind() -> Self

Creates a new blind sparse trie.

Examples

use reth_trie_sparse::RevealableSparseTrie;

let trie = <RevealableSparseTrie>::blind();
assert!(trie.is_blind());
let trie = <RevealableSparseTrie>::default();
assert!(trie.is_blind());

pub fn blind_from(trie: T) -> Self

Creates a new blind sparse trie, clearing and later reusing the given RevealableSparseTrie.

pub const fn is_blind(&self) -> bool

Returns true if the sparse trie has no revealed nodes.

pub const fn is_revealed(&self) -> bool

Returns true if the sparse trie is revealed.

pub const fn as_revealed_ref(&self) -> Option<&T>

Returns an immutable reference to the underlying revealed sparse trie.

Returns None if the trie is blinded.

pub fn as_revealed_mut(&mut self) -> Option<&mut T>

Returns a mutable reference to the underlying revealed sparse trie.

Returns None if the trie is blinded.

pub fn root(&mut self, new_epoch: TrieNodeEpoch) -> Option<B256>

Calculates the root hash of the trie.

This will update any remaining dirty nodes before computing the root hash. “dirty” nodes are nodes that need their hashes to be recomputed because one or more of their children’s hashes have changed.

Returns

• Some(B256) with the calculated root hash if the trie is revealed.
• None if the trie is still blind.

pub fn is_root_cached(&self) -> bool

Returns true if the root node is cached and does not need any recomputation.

pub fn root_with_updates( &mut self, new_epoch: TrieNodeEpoch, ) -> Option<(B256, SparseTrieUpdates)>

Returns the root hash along with any accumulated update information.

This is useful for when you need both the root hash and information about what nodes were modified, which can be used to efficiently update an external database.

Returns

An Option tuple consisting of:

• The trie root hash (B256).
• A SparseTrieUpdates structure containing information about updated nodes.
• None if the trie is still blind.

pub fn clear(&mut self)

Clears this trie, setting it to a blind state.

If this instance was revealed, or was itself a Blind with a pre-allocated RevealableSparseTrie, this will set to Blind carrying a cleared pre-allocated RevealableSparseTrie.

impl<T: SparseTrieTrait + Default> RevealableSparseTrie<T>

pub fn update_leaves( &mut self, updates: &mut B256Map<LeafUpdate>, proof_required_fn: impl FnMut(B256, ProofV2TargetParent), ) -> SparseTrieResult<()>

Applies batch leaf updates to the sparse trie.

For blind tries, all updates are kept in the map and proof targets are emitted for every key (with no known parent since nothing is revealed).

For revealed tries, delegates to the inner implementation which will:

• Apply updates where possible
• Keep blocked updates in the map
• Emit proof targets for blinded paths

Trait Implementations

impl<T: Clone> Clone for RevealableSparseTrie<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug> Debug for RevealableSparseTrie<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Default> Default for RevealableSparseTrie<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T: Eq> Eq for RevealableSparseTrie<T>

impl<T: PartialEq> PartialEq for RevealableSparseTrie<T>

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<T: PartialEq> StructuralPartialEq for RevealableSparseTrie<T>

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 16 bytes

Size for each variant:

• Blind: 8 bytes
• Revealed: 8 bytes