預期標識符，但獲得保留關鍵字“參考”產品公共參考；^——–^

大家好，我是初學者。我想做一個創建契約的功能。

我在網際網路上找到了一個範例，但給了我一個錯誤，所以我不知道該怎麼辦。

任何人都可以幫助我嗎？

pragma solidity ^0.5.0;

contract Product {
   Factory public factory;
   Product public reference;//**here's the error**
function Product(Product _reference, Factory _factory){
   reference = _reference;
   factory = _factory;
}

function haveFactoryCreateProductWithReferenceToThis() public {
   emit ProductCreated(factory.createNewProduct(this));
}

event ProductCreated(Product indexed product);
}

contract Factory{
   function createNewProduct(Product _reference) public returns (Product) {
       Product p = new Product(_reference, this);
       return p;
   }
}

pragma solidity ^0.5.0;

contract Product {
   Factory public factory;
   Product public x;
constructor(Product _reference, Factory _factory) public{
   x = _reference;
   factory = _factory;
}

function haveFactoryCreateProductWithReferenceToThis() public {
   emit ProductCreated(factory.createNewProduct(this));
}

event ProductCreated(Product indexed product);
}

contract Factory{
   function createNewProduct(Product _reference) public returns (Product) {
       Product p = new Product(_reference, this);
       return p;
   }
}

嘿，我做了一個小改動，現在可以使用了！

引用自：https://ethereum.stackexchange.com/questions/73038