我正在尝试执行pyethereum的代码，但是当我在其中分析代码时
pyethereum/Ethereum/hybrid_casper/consenus.py
我不明白'NULL_SENDER'值的定义位置以及该state.config['NULL_SENDER]的执行方式。
key, account = state.config['NULL_SENDER'], privtoaddr(state.config['NULL_SENDER'])
答案 0 :(得分：0)
让我们浏览所有代码。
<field name="x_impuestosoaportes" domain="[('x_name','in', x_impuestosapagar and x_impuestosapagar[0] and x_impuestosapagar[0][2])]"/>
<field name="x_importe"/>
<field name="x_empresa" invisible="1"/>
<field name="x_impuestosapagar" invisible="1"/>
<field name="x_vencimiento"/>
我们可以看到此代码很可能是由多个程序导入的！ https://github.com/ethereum/pyethereum/blob/develop/ethereum/hybrid_casper/chain.py
如果我们在chain.py中看到该函数的用法，则from ethereum import utils, transactions
from ethereum.common import update_block_env_variables
from ethereum.messages import apply_transaction
from ethereum.hybrid_casper import casper_utils
from ethereum.utils import privtoaddr
# Block initialization state transition
def initialize(state, block=None):
config = state.config
state.txindex = 0
state.gas_used = 0
state.bloom = 0
state.receipts = []
if block is not None:
update_block_env_variables(state, block)
# Initalize the next epoch in the Casper contract
if state.block_number % state.config['EPOCH_LENGTH'] == 0 and state.block_number != 0:
key, account = state.config['NULL_SENDER'], privtoaddr(state.config['NULL_SENDER'])
data = casper_utils.casper_translator.encode('initialize_epoch', [state.block_number // state.config['EPOCH_LENGTH']])
transaction = transactions.Transaction(state.get_nonce(account), 0, 3141592,
state.config['CASPER_ADDRESS'], 0, data).sign(key)
success, output = apply_transaction(state, transaction)
assert success
if state.is_DAO(at_fork_height=True):
for acct in state.config['CHILD_DAO_LIST']:
state.transfer_value(
acct,
state.config['DAO_WITHDRAWER'],
state.get_balance(acct))
if state.is_METROPOLIS(at_fork_height=True):
state.set_code(utils.normalize_address(
config["METROPOLIS_STATEROOT_STORE"]), config["METROPOLIS_GETTER_CODE"])
state.set_code(utils.normalize_address(
config["METROPOLIS_BLOCKHASH_STORE"]), config["METROPOLIS_GETTER_CODE"])
用state来满足，即为self.state。
此函数返回一个用self.state = self.mk_poststate_of_blockhash(self.db.get(b'head_hash'))制作的State对象，该对象可以变成字典。这最有可能意味着它正在获取与名为“ NULL_SENDER”的键相对应的值。