Struct revm::EVM

pub struct EVM<DB> {
    pub env: Env,
    pub db: Option<DB>,
}

Struct that takes Database and enabled transact to update state dirrectly to database. additionaly it allows user to set all environment parameters.

Parameters that can be set are devided between Config, Block and Transaction(tx)

For transacting on EVM you can call transact_commit that will automatically apply changes to db.

You can do a lot with rust and traits. For Database abstractions that we need you can implement, Database, DatabaseRef or Database+DatabaseCommit and they enable functionality depending on what kind of handling of struct you want.

• Database trait has mutable self in its functions. It is usefull if on get calls you want to modify your cache or update some statistics. They enable transact and inspect functions
• DatabaseRef takes reference on object, this is useful if you only have reference on state and dont want to update anything on it. It enabled transact_ref and inspect_ref functions
• Database+DatabaseCommit allow’s dirrectly commiting changes of transaction. it enabled transact_commit and inspect_commit

Fields

env: Env

db: Option<DB>

Implementations

impl<DB: Database + DatabaseCommit> EVM<DB>

pub fn transact_commit(&mut self) -> (Return, TransactOut, u64)

Execute transaction and apply result to database

pub fn inspect_commit<INSP: Inspector<DB>>(
    &mut self,
    inspector: INSP
) -> (Return, TransactOut, u64)

Inspect transaction and commit changes to database.

impl<DB: Database> EVM<DB>

pub fn transact(&mut self) -> (Return, TransactOut, u64, Map<H160, Account>)

Execute transaction without writing to DB, return change state.

pub fn inspect<INSP: Inspector<DB>>(
    &mut self,
    inspector: INSP
) -> (Return, TransactOut, u64, Map<H160, Account>)

Execute transaction with given inspector, without wring to DB. Return change state.

impl<'a, DB: DatabaseRef> EVM<DB>

pub fn transact_ref(&mut self) -> (Return, TransactOut, u64, Map<H160, Account>)

Execute transaction without writing to DB, return change state.

pub fn inspect_ref<INSP: Inspector<RefDBWrapper<'a>>>(
    &'a mut self,
    inspector: INSP
) -> (Return, TransactOut, u64, Map<H160, Account>)

Execute transaction with given inspector, without wring to DB. Return change state.

impl<DB> EVM<DB>

pub fn new() -> Self

pub fn database(&mut self, db: DB)

pub fn db(&mut self) -> Option<&mut DB>

pub fn take_db(&mut self) -> DB

Trait Implementations

impl<DB> Default for EVM<DB>

fn default() -> Self

Returns the “default value” for a type.