Enum SparseTrie 

pub enum SparseTrie<T = SerialSparseTrie> {
    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 SparseTrie can optionally carry with it a cleared SerialSparseTrie. 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: SparseTrieInterface + Default> SparseTrie<T>

pub fn revealed_empty() -> Self

Creates a new revealed but empty sparse trie with SparseNode::Empty as root node.

Examples

use reth_trie_sparse::{provider::DefaultTrieNodeProvider, SerialSparseTrie, SparseTrie};

let trie = SparseTrie::<SerialSparseTrie>::revealed_empty();
assert!(!trie.is_blind());

pub fn reveal_root( &mut self, root: TrieNode, masks: TrieMasks, 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 retain_updates flag controls whether changes to the trie structure should be tracked.

Returns

A mutable reference to the underlying SparseTrieInterface.

impl<T: SparseTrieInterface> SparseTrie<T>

pub const fn blind() -> Self

Creates a new blind sparse trie.

Examples

use reth_trie_sparse::{provider::DefaultTrieNodeProvider, SerialSparseTrie, SparseTrie};

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

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 wipe(&mut self) -> SparseTrieResult<()>

Wipes the trie by removing all nodes and values, and resetting the trie to only contain an empty root node.

Note: This method will error if the trie is blinded.

pub fn root(&mut self) -> 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 root_with_updates(&mut self) -> 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(self) -> Self

Returns a SparseTrie::Blind based on this one. If this instance was revealed, or was itself a Blind with a pre-allocated SparseTrieInterface, this will return a Blind carrying a cleared pre-allocated SparseTrieInterface.

pub fn update_leaf( &mut self, path: Nibbles, value: Vec<u8>, provider: impl TrieNodeProvider, ) -> SparseTrieResult<()>

Updates (or inserts) a leaf at the given key path with the specified RLP-encoded value.

Errors

Returns an error if the trie is still blind, or if the update fails.

pub fn remove_leaf( &mut self, path: &Nibbles, provider: impl TrieNodeProvider, ) -> SparseTrieResult<()>

Removes a leaf node at the specified key path.

Errors

Returns an error if the trie is still blind, or if the leaf cannot be removed

Trait Implementations

impl<T: Debug> Debug for SparseTrie<T>

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

Formats the value using the given formatter.

impl<T: Default> Default for SparseTrie<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T: PartialEq> PartialEq for SparseTrie<T>

fn eq(&self, other: &SparseTrie<T>) -> bool

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T: Eq> Eq for SparseTrie<T>

impl<T> StructuralPartialEq for SparseTrie<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