Gold(G)

Token

0xfcaf20485278...1437f7303505

HomesteadContract #19KExact Bytecode MatchEdit this contract

Deployed June 19, 2016 (10 years ago)Block 1,733,382

Gold (G), a 5 decimal token holding just 1.5 whole units, deployed 19 June 2016.

Homestead EraVerified Source

Historical Significance

Gold is an approval and transfer token whose creator minted 150,000 base units against 5 decimals, so the entire supply is one and a half whole G. It has no owner, no minting path and no freeze, so the opening balance is all there will ever be. Alongside the standard transfer and allowance calls it carries approveAndCall, which notifies a spending contract in the same transaction that approves it.

Context

Deployed weeks after the DAO hard fork debate began, in the wave of tutorial derived tokens that followed.

Token Information

Token Name

Gold

Symbol

Decimals

Key Facts

Deployer

0xab1d5c...6e5de0

Deployment Block

1,733,382

Deployment Date

Jun 19, 2016, 07:39 PM

Code Size

1.6 KB

Gas at Deploy

658,434

Deployment Transaction: 0x1994105726668bb3...f069e5f060eca101

Description

A token from the ethereum.org tutorial. Balances sit in a public balanceOf mapping and transfer(to, value) moves them, throwing rather than returning false when the sender is short and checking the recipient's balance for overflow before adding to it. An allowance mapping records what each spender has been authorised for. ApproveAndCall sets the allowance and calls receiveApproval on the spender in the same transaction, so a spending contract learns of its allowance at the moment it is granted. There is no owner and no way to create further units: the supply written at deployment is the whole supply. It was deployed as Gold, with the symbol G and an opening supply of 150,000 base units at 5 decimal places and it answers standard() with the string Token 0.1, the label the tutorial used before ERC-20 had a number.

Source Verified

SolidityExact bytecode match(1,680 bytes)

Compiler: v0.3.3+

View verification proof

Exact runtime bytecode match. soljson v0.3.3+commit.4dc1cb14 (Emscripten), optimizer ON. 82 identical siblings.

Historian Categories

Token

Heuristic Analysis

The following characteristics were detected through bytecode analysis and may not be accurate.

Detected Type: Token

Has ERC-20-like patterns

Homestead Era

The first planned hard fork. Removed the canary contract, adjusted gas costs.

Block span: 1,150,000 — 1,919,999

March 14, 2016 — July 20, 2016

Bytecode Overview

Opcodes1,680

Unique Opcodes126

Jump Instructions79

Storage Operations30

Verified Source Available

Source verified through compiler archaeology and exact bytecode matching.

View Verification Proof

Show source code (Solidity)

contract tokenRecipient { function receiveApproval(address _from, uint256 _value, address _token, bytes _extraData); }

contract MyToken {
    string public standard = "Token 0.1";
    string public name;
    string public symbol;
    uint8 public decimals;
    uint256 public totalSupply;
    mapping (address => uint256) public balanceOf;
    mapping (address => mapping (address => uint256)) public allowance;

    event Transfer(address indexed from, address indexed to, uint256 value);

    function MyToken(uint256 initialSupply, string tokenName, uint8 decimalUnits, string tokenSymbol) {
        balanceOf[msg.sender] = initialSupply;
        totalSupply = initialSupply;
        name = tokenName;
        symbol = tokenSymbol;
        decimals = decimalUnits;
    }

    function transfer(address _to, uint256 _value) {
        if (balanceOf[msg.sender] < _value) throw;
        if (balanceOf[_to] + _value < balanceOf[_to]) throw;
        balanceOf[msg.sender] -= _value;
        balanceOf[_to] += _value;
        Transfer(msg.sender, _to, _value);
    }

    function approveAndCall(address _spender, uint256 _value, bytes _extraData) returns (bool success) {
        allowance[msg.sender][_spender] = _value;
        tokenRecipient spender = tokenRecipient(_spender);
        spender.receiveApproval(msg.sender, _value, this, _extraData);
        return true;
    }

    function transferFrom(address _from, address _to, uint256 _value) returns (bool success) {
        if (balanceOf[_from] < _value) throw;
        if (balanceOf[_to] + _value < balanceOf[_to]) throw;
        if (_value > allowance[_from][msg.sender]) throw;
        balanceOf[_from] -= _value;
        balanceOf[_to] += _value;
        allowance[_from][msg.sender] -= _value;
        Transfer(_from, _to, _value);
        return true;
    }

    function () {
        throw;
    }
}