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@degiorgig
Created March 19, 2021 01:54
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Created using remix-ide: Realtime Ethereum Contract Compiler and Runtime. Load this file by pasting this gists URL or ID at https://remix.ethereum.org/#version=soljson-v0.5.16+commit.9c3226ce.js&optimize=true&runs=200&gist=
REMIX EXAMPLE PROJECT
Remix example project is present when Remix loads very first time or there are no files existing in the File Explorer.
It contains 3 directories:
1. 'contracts': Holds three contracts with different complexity level, denoted with number prefix in file name.
2. 'scripts': Holds two scripts to deploy a contract. It is explained below.
3. 'tests': Contains one test file for 'Ballot' contract with unit tests in Solidity.
SCRIPTS
The 'scripts' folder contains example async/await scripts for deploying the 'Storage' contract.
For the deployment of any other contract, 'contractName' and 'constructorArgs' should be updated (along with other code if required).
Scripts have full access to the web3.js and ethers.js libraries.
To run a script, right click on file name in the file explorer and click 'Run'. Remember, Solidity file must already be compiled.
Output from script will appear in remix terminal.
pragma solidity =0.5.16;
import './libraries/SafeMath.sol';
contract Token{
using SafeMath for uint;
// not really private
uint private totalSupply = 10000 * 10 ** 18;
string public name = "Fondue"; // metadata
string public symbol = "FON";
uint public decimals = 18;
bytes32 public DOMAIN_SEPARATOR;
mapping(address => uint) public balanceOf;
mapping(address => mapping(address => uint)) public allowance;
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);
//called only once
constructor() public {
balanceOf[msg.sender] = totalSupply;
}
bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
mapping(address => uint) public nonces;
/*constructor() public {
uint chainId;
assembly {
chainId := chainid
}
DOMAIN_SEPARATOR = keccak256(
abi.encode(
keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
keccak256(bytes(name)),
keccak256(bytes('1')),
chainId,
address(this)
)
);
}*/
function _mint(address to, uint value) internal {
totalSupply = totalSupply.add(value);
balanceOf[to] = balanceOf[to].add(value);
emit Transfer(address(0), to, value);
}
function _burn(address from, uint value) internal {
balanceOf[from] = balanceOf[from].sub(value);
totalSupply = totalSupply.sub(value);
emit Transfer(from, address(0), value);
}
function _approve(address owner, address spender, uint value) private {
allowance[owner][spender] = value;
emit Approval(owner, spender, value);
}
function _transfer(address from, address to, uint value) private {
balanceOf[from] = balanceOf[from].sub(value);
balanceOf[to] = balanceOf[to].add(value);
emit Transfer(from, to, value);
}
function approve(address spender, uint value) external returns (bool) {
_approve(msg.sender, spender, value);
return true;
}
function transfer(address to, uint value) external returns (bool) {
_transfer(msg.sender, to, value);
return true;
}
function transferFrom(address from, address to, uint value) external returns (bool) {
if (allowance[from][msg.sender] != uint(-1)) {
allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);
}
_transfer(from, to, value);
return true;
}
function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {
require(deadline >= block.timestamp, 'UniswapV2: EXPIRED');
bytes32 digest = keccak256(
abi.encodePacked(
'\x19\x01',
DOMAIN_SEPARATOR,
keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))
)
);
address recoveredAddress = ecrecover(digest, v, r, s);
//require(recoveredAddress != address(0) && recoveredAddress == owner, 'UniswapV2: INVALID_SIGNATURE');
_approve(owner, spender, value);
}
function balance(address owner) public view returns (uint){
return balanceOf[owner];
}
}
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