Chanutg

import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import * as serviceWorker from './serviceWorker';

import { Drizzle } from "drizzle";
import HelloWorld from "./contracts/HelloWorld.json";

const options = {

Chanutg

pragma solidity ^0.5.0;

contract HelloWorld {
    string public sentence;
    string public userName;

    constructor() public {
        sentence = "HelloWorld !";
        userName = "Guillaume";
    }

Chanutg

    function concat(string memory _base, string memory _value) internal pure returns (string memory) {
           bytes memory _baseBytes = bytes(_base);
           bytes memory _valueBytes = bytes(_value);

           string memory _tmpValue = new string(_baseBytes.length + _valueBytes.length);
           bytes memory _newValue = bytes(_tmpValue);

           uint i;
           uint j;

Chanutg

const Migrations = artifacts.require("Migrations");
const HelloWorld = artifacts.require("HelloWorld");

module.exports = function(deployer) {
  deployer.deploy(Migrations);
  deployer.deploy(HelloWorld);
};

Chanutg

pragma solidity ^0.5.0;

contract HelloWorld {

    string public sentence;

    constructor() public {
        sentence = "HelloWorld !";
    }