Counter.sol

// SPDX-License-Identifier: MIT
pragma solidity >=0.7.0 <0.9.0;

import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/utils/Counters.sol";

contract AMM is ReentrancyGuard{
    using Counters for Counters.Counter;
    Counters.Counter private caseID;

    struct SomeXYZData {
        uint256 caseID;
        address from;
    }

    mapping(uint256 => SomeXYZData) public xyzData;

    function createData() public nonReentrant
    {
        caseID.increment();

        SomeXYZData storage currData = xyzData[caseID.current()];

        currData.caseID = caseID.current();
        currData.from = msg.sender;
    }
}