30 lines
909 B
Rust
30 lines
909 B
Rust
|
use hash::H256;
|
||
|
|
use rlp::SHA3_NULL_RLP;
|
||
|
|
|
||
|
|
/// A key-value datastore implemented as a database-backed modified Merkle tree.
|
||
|
|
pub trait Trie {
|
||
|
|
/// Return the root of the trie.
|
||
|
|
fn root(&self) -> &H256;
|
||
|
|
|
||
|
|
/// Is the trie empty?
|
||
|
|
fn is_empty(&self) -> bool { *self.root() == SHA3_NULL_RLP }
|
||
|
|
|
||
|
|
/// Does the trie contain a given key?
|
||
|
|
fn contains(&self, key: &[u8]) -> bool;
|
||
|
|
|
||
|
|
/// What is the value of the given key in this trie?
|
||
|
|
fn get<'a, 'key>(&'a self, key: &'key [u8]) -> Option<&'a [u8]> where 'a: 'key;
|
||
|
|
}
|
||
|
|
|
||
|
|
/// A key-value datastore implemented as a database-backed modified Merkle tree.
|
||
|
|
pub trait TrieMut: Trie {
|
||
|
|
/// Insert a `key`/`value` pair into the trie. An `empty` value is equivalent to removing
|
||
|
|
/// `key` from the trie.
|
||
|
|
fn insert(&mut self, key: &[u8], value: &[u8]);
|
||
|
|
|
||
|
|
/// Remove a `key` from the trie. Equivalent to making it equal to the empty
|
||
|
|
/// value.
|
||
|
|
fn remove(&mut self, key: &[u8]);
|
||
|
|
}
|
||
|
|
|