Created
April 1, 2018 02:06
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pragma solidity ^0.4.18; | |
// import "./EIP20Interface.sol"; | |
import "github.com/ConsenSys/Tokens/contracts/eip20/EIP20Interface.sol"; | |
contract EIP20 is EIP20Interface { | |
uint256 constant private MAX_UINT256 = 2**256 - 1; | |
mapping (address => uint256) public balances; | |
mapping (address => mapping (address => uint256)) public allowed; | |
/* | |
NOTE: | |
The following variables are OPTIONAL vanities. One does not have to include them. | |
They allow one to customise the token contract & in no way influences the core functionality. | |
Some wallets/interfaces might not even bother to look at this information. | |
*/ | |
string public name; //fancy name: eg Simon Bucks | |
uint8 public decimals; //How many decimals to show. | |
string public symbol; //An identifier: eg SBX | |
function EIP20( | |
uint256 _initialAmount, | |
string _tokenName, | |
uint8 _decimalUnits, | |
string _tokenSymbol | |
) public { | |
balances[msg.sender] = _initialAmount; // Give the creator all initial tokens | |
totalSupply = _initialAmount; // Update total supply | |
name = _tokenName; // Set the name for display purposes | |
decimals = _decimalUnits; // Amount of decimals for display purposes | |
symbol = _tokenSymbol; // Set the symbol for display purposes | |
} | |
function transfer(address _to, uint256 _value) public returns (bool success) { | |
require(balances[msg.sender] >= _value); | |
balances[msg.sender] -= _value; | |
balances[_to] += _value; | |
Transfer(msg.sender, _to, _value); | |
return true; | |
} | |
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) { | |
uint256 allowance = allowed[_from][msg.sender]; | |
require(balances[_from] >= _value && allowance >= _value); | |
balances[_to] += _value; | |
balances[_from] -= _value; | |
if (allowance < MAX_UINT256) { | |
allowed[_from][msg.sender] -= _value; | |
} | |
Transfer(_from, _to, _value); | |
return true; | |
} | |
function balanceOf(address _owner) public view returns (uint256 balance) { | |
return balances[_owner]; | |
} | |
function approve(address _spender, uint256 _value) public returns (bool success) { | |
allowed[msg.sender][_spender] = _value; | |
Approval(msg.sender, _spender, _value); | |
return true; | |
} | |
function allowance(address _owner, address _spender) public view returns (uint256 remaining) { | |
return allowed[_owner][_spender]; | |
} | |
} |
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