I got error in my smart contract,
/Pool.sol:10:1: DeclarationError: Identifier already declared. import './ERC20.sol'; ^------------------------------^ Token.sol:10:1: The previous declaration is here: contract ERC20 { ^ (Relevant source part starts here and spans across multiple lines).
Token.sol is using ERC20 contract inline and not importing it, while Pool.sol is importing Token.sol, ERC20.sol
I tried changing name of ERC20 to ERC20-new throughout the Token.sol file only so it could fix the conflict still faced some issues
Pool.sol
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.12;
pragma experimental ABIEncoderV2;
import './Token.sol';
import './Initializable.sol';
import './SafeMath.sol';
import './interfaces/IERC20.sol';
import './interfaces/ERC20.sol';
import './interfaces/IFactory.sol';
import './interfaces/IPool.sol';
import './interfaces/ISettlement.sol';
import './interfaces/IOracle.sol';
contract Pool is Initializable {
using SafeMath for uint;
bytes4 private constant SELECTOR = bytes4(keccak256(bytes('transfer(address,uint256)')));
address public factory;
address public baseToken;
uint public baseTokenDecimals;
address public oracle;
uint public oracleDecimals;
uint public baseTokenTargetAmount;
uint public baseTokenBalance;
uint public liquidityParameter;
bool public tradeEnabled;
bool public depositEnabled;
bool public withdrawEnabled;
Token.sol
pragma solidity >=0.7.5;
import './SafeMath.sol';
interface tokenRecipient {
function receiveApproval(address _from, uint256 _value, address _token, bytes calldata _extraData) external;
}
contract ERC20 {
mapping (address => uint256) public balanceOf;
mapping (address => mapping (address => uint256)) public allowance;
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
function _transfer(address _from, address _to, uint _value) internal {
require(_to != address(0x0));
require(balanceOf[_from] >= _value);
require(balanceOf[_to] + _value >= balanceOf[_to]);
uint previousBalances = balanceOf[_from] + balanceOf[_to];
balanceOf[_from] -= _value;
balanceOf[_to] += _value;
emit Transfer(_from, _to, _value);
assert(balanceOf[_from] + balanceOf[_to] == previousBalances);
}
function transfer(address _to, uint256 _value) public returns (bool success) {
_transfer(msg.sender, _to, _value);
return true;
}
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
require(_value <= allowance[_from][msg.sender]); // Check allowance
allowance[_from][msg.sender] -= _value;
_transfer(_from, _to, _value);
return true;
}
function approve(address _spender, uint256 _value) public
returns (bool success) {
allowance[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
function approveAndCall(address _spender, uint256 _value, bytes memory _extraData)
public
returns (bool success) {
tokenRecipient spender = tokenRecipient(_spender);
if (approve(_spender, _value)) {
spender.receiveApproval(msg.sender, _value, address(this), _extraData);
return true;
}
}
}
