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bodrovis/ERC.sol

Last active January 16, 2023 15:58
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  1. bodrovis revised this gist Jan 16, 2023. 1 changed file with 160 additions and 0 deletions.
    160 changes: 160 additions & 0 deletions ERC.sol
    View file
    Original file line number Diff line number Diff line change
    @@ -11,3 +11,163 @@ interface IERC20Metadata is IERC20 {

    function decimals() external view returns (uint8);
    }

    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)

    pragma solidity ^0.8.0;

    import "./IERC20.sol";
    import "./extensions/IERC20Metadata.sol";
    import "../../utils/Context.sol";

    contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;

    constructor(string memory name_, string memory symbol_) {
    _name = name_;
    _symbol = symbol_;
    }

    function name() public view virtual override returns (string memory) {
    return _name;
    }

    function symbol() public view virtual override returns (string memory) {
    return _symbol;
    }

    function decimals() public view virtual override returns (uint8) {
    return 18;
    }

    function totalSupply() public view virtual override returns (uint256) {
    return _totalSupply;
    }

    function balanceOf(address account) public view virtual override returns (uint256) {
    return _balances[account];
    }
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
    address owner = _msgSender();
    _transfer(owner, to, amount);
    return true;
    }

    function allowance(address owner, address spender) public view virtual override returns (uint256) {
    return _allowances[owner][spender];
    }

    function approve(address spender, uint256 amount) public virtual override returns (bool) {
    address owner = _msgSender();
    _approve(owner, spender, amount);
    return true;
    }

    function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
    address spender = _msgSender();
    _spendAllowance(from, spender, amount);
    _transfer(from, to, amount);
    return true;
    }


    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
    address owner = _msgSender();
    _approve(owner, spender, allowance(owner, spender) + addedValue);
    return true;
    }
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
    address owner = _msgSender();
    uint256 currentAllowance = allowance(owner, spender);
    require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
    unchecked {
    _approve(owner, spender, currentAllowance - subtractedValue);
    }

    return true;
    }

    function _transfer(address from, address to, uint256 amount) internal virtual {
    require(from != address(0), "ERC20: transfer from the zero address");
    require(to != address(0), "ERC20: transfer to the zero address");

    _beforeTokenTransfer(from, to, amount);

    uint256 fromBalance = _balances[from];
    require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
    unchecked {
    _balances[from] = fromBalance - amount;
    // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
    // decrementing then incrementing.
    _balances[to] += amount;
    }

    emit Transfer(from, to, amount);

    _afterTokenTransfer(from, to, amount);
    }

    function _mint(address account, uint256 amount) internal virtual {
    require(account != address(0), "ERC20: mint to the zero address");

    _beforeTokenTransfer(address(0), account, amount);

    _totalSupply += amount;
    unchecked {
    // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
    _balances[account] += amount;
    }
    emit Transfer(address(0), account, amount);

    _afterTokenTransfer(address(0), account, amount);
    }

    function _burn(address account, uint256 amount) internal virtual {
    require(account != address(0), "ERC20: burn from the zero address");

    _beforeTokenTransfer(account, address(0), amount);

    uint256 accountBalance = _balances[account];
    require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
    unchecked {
    _balances[account] = accountBalance - amount;
    // Overflow not possible: amount <= accountBalance <= totalSupply.
    _totalSupply -= amount;
    }

    emit Transfer(account, address(0), amount);

    _afterTokenTransfer(account, address(0), amount);
    }

    function _approve(address owner, address spender, uint256 amount) internal virtual {
    require(owner != address(0), "ERC20: approve from the zero address");
    require(spender != address(0), "ERC20: approve to the zero address");

    _allowances[owner][spender] = amount;
    emit Approval(owner, spender, amount);
    }

    function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
    uint256 currentAllowance = allowance(owner, spender);
    if (currentAllowance != type(uint256).max) {
    require(currentAllowance >= amount, "ERC20: insufficient allowance");
    unchecked {
    _approve(owner, spender, currentAllowance - amount);
    }
    }
    }

    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual {}

    function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
    }

  2. bodrovis created this gist Jan 16, 2023.
    13 changes: 13 additions & 0 deletions ERC.sol
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,13 @@
    // SPDX-License-Identifier: MIT

    pragma solidity ^0.8.0;

    import "../IERC20.sol";

    interface IERC20Metadata is IERC20 {
    function name() external view returns (string memory);

    function symbol() external view returns (string memory);

    function decimals() external view returns (uint8);
    }