Struct patricia_trie::FatDBMut

pub struct FatDBMut<'db> { /* fields omitted */ }

A mutable Trie implementation which hashes keys and uses a generic HashDB backing database. Additionaly it stores inserted hash-key mappings for later retrieval.

Use it as a Trie or TrieMut trait object.

Methods

impl<'db> FatDBMut<'db>

fn new(db: &'db mut HashDB, root: &'db mut H256) -> Self

Create a new trie with the backing database db and empty root Initialise to the state entailed by the genesis block. This guarantees the trie is built correctly.

fn from_existing(db: &'db mut HashDB, root: &'db mut H256) -> Result<Self>

Create a new trie with the backing database db and root.

Returns an error if root does not exist.

fn db(&self) -> &HashDB

Get the backing database.

fn db_mut(&mut self) -> &mut HashDB

Get the backing database.

Trait Implementations

impl<'db> TrieMut for FatDBMut<'db>

fn root(&mut self) -> &H256

Return the root of the trie.

fn is_empty(&self) -> bool

Is the trie empty?

fn contains(&self, key: &[u8]) -> Result<bool>

Does the trie contain a given key?

fn get<'a, 'key>(&'a self, key: &'key [u8]) -> Result<Option<DBValue>> where
    'a: 'key, 

What is the value of the given key in this trie?

fn insert(&mut self, key: &[u8], value: &[u8]) -> Result<Option<DBValue>>

Insert a key/value pair into the trie. An empty value is equivalent to removing key from the trie. Returns the old value associated with this key, if it existed.

fn remove(&mut self, key: &[u8]) -> Result<Option<DBValue>>

Remove a key from the trie. Equivalent to making it equal to the empty value. Returns the old value associated with this key, if it existed.