Solidity contract to demo try / catch statements and error retrieval.

DemoTryCatch.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract HelloWorld {
    function showMessage() public pure returns (string memory) {
        return "Hello, World!";
    }
}

contract HelloWorldFactory {
    mapping (address => HelloWorld) public contracts;
    string public errorMessage;
    bytes public errorData;

    function createHelloWorld() public {
        try new HelloWorld()
            returns (HelloWorld newContract)
        {
            contracts[msg.sender] = newContract;
        } catch Error(string memory reason) {
            errorMessage = reason;
        } catch (bytes memory data) {
            errorData = data;
        }
    }
}