Contract Name:
Vyper_contract
Contract Source Code:
File 1 of 1 : Vyper_contract
#pragma version >0.3.10
from ethereum.ercs import IERC20
from ethereum.ercs import IERC20Detailed
implements: IERC20
implements: IERC20Detailed
name: public(String[32])
symbol: public(String[32])
decimals: public(uint8)
# NOTE: By declaring `balanceOf` as public, vyper automatically generates a 'balanceOf()' getter
# method to allow access to account balances.
balanceOf: public(HashMap[address, uint256])
# By declaring `allowance` as public, vyper automatically generates the `allowance()` getter
allowance: public(HashMap[address, HashMap[address, uint256]])
# By declaring `totalSupply` as public, we automatically create the `totalSupply()` getter
totalSupply: public(uint256)
@deploy
def __init__(_name: String[32], _symbol: String[32], _decimals: uint8, _supply: uint256):
init_supply: uint256 = _supply * 10 ** convert(_decimals, uint256)
self.name = _name
self.symbol = _symbol
self.decimals = _decimals
self.balanceOf[msg.sender] = init_supply
self.totalSupply = init_supply
log IERC20.Transfer(empty(address), msg.sender, init_supply)
@external
def transfer(_to : address, _value : uint256) -> bool:
"""
@dev Transfer token for a specified address
@param _to The address to transfer to.
@param _value The amount to be transferred.
"""
# NOTE: vyper does not allow underflows
# so the following subtraction would revert on insufficient balance
self.balanceOf[msg.sender] -= _value
self.balanceOf[_to] += _value
log IERC20.Transfer(msg.sender, _to, _value)
return True
@external
def transferFrom(_from : address, _to : address, _value : uint256) -> bool:
"""
@dev Transfer tokens from one address to another.
@param _from address The address which you want to send tokens from
@param _to address The address which you want to transfer to
@param _value uint256 the amount of tokens to be transferred
"""
# NOTE: vyper does not allow underflows
# so the following subtraction would revert on insufficient balance
self.balanceOf[_from] -= _value
self.balanceOf[_to] += _value
# NOTE: vyper does not allow underflows
# so the following subtraction would revert on insufficient allowance
self.allowance[_from][msg.sender] -= _value
log IERC20.Transfer(_from, _to, _value)
return True
@external
def approve(_spender : address, _value : uint256) -> bool:
"""
@dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
@param _spender The address which will spend the funds.
@param _value The amount of tokens to be spent.
"""
self.allowance[msg.sender][_spender] = _value
log IERC20.Approval(msg.sender, _spender, _value)
return True
@internal
def _burn(_to: address, _value: uint256):
"""
@dev Internal function that burns an amount of the token of a given
account.
@param _to The account whose tokens will be burned.
@param _value The amount that will be burned.
"""
assert _to != empty(address)
self.totalSupply -= _value
self.balanceOf[_to] -= _value
log IERC20.Transfer(_to, empty(address), _value)
@external
def burn(_value: uint256):
"""
@dev Burn an amount of the token of msg.sender.
@param _value The amount that will be burned.
"""
self._burn(msg.sender, _value)