Hi @thecil. I would appreciate your help!
Would you be able to create a github repo for this project? I might need to check your migration files and smart contract files
Carlos Z
I made the project with solidity 0.6.1 and I am not able to set the proxy owner with the initilization function call. Even if I copy the example code from Github I get troubles. I copy everything exactly with exception of the solidity version I use, and I also delete the “owner = msg.sender” line from the Proxy constructor because I want to set the owner with the function “initialize()”. After calling “initialize()” owner of proxy is still “0x0000000000000000”. Anyone has the same issue and knows how to solve this ?
Hi Guys,
I’m struggling to install Atom, I don’t know what version I should install, as now we’re using solidity version 0.8.20, not 0.5.1, as in Filip’s lecture, also which truffle version I should install in the command prompt?
I have installed Atom
I used the link provided is the lecture, and selected the atom-windows.zip. but my code, not colored like in the lecture.
Also my command prompt not working the same as the lecture.
I’m in part 6 but when I try to develop the contract on command prompt it freeze
I’m using windows.
My code:
// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;
contract Storage{
mapping(string => uint256) _uintStorage;
mapping(string => address) _addressStorage;
mapping(string => bool) _boolStorage;
mapping(string => string) _stringStorage;
mapping(string => bytes4) _bytesStorage;
address public owner;
bool public _initialized;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;
import "./Storage.sol";
contract Dogs is Storage{
modifier onlyOnwer(){
require(msg.sender == owner);
_;
}
constructor () public{
owner == msg.sender;
}
function getNumberOfDogs() public view returns (uint256){
return _uintStorage["Dogs"];
}
function setNumberOfDogs(uint256 toSet) public{
_uintStorage["Dogs"] = toSet;
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;
import "./Storage.sol";
contract Proxy is Storage{
address currentAddress;
constructor(address _currentAddress) public{
currentAddress = _currentAddress;
}
function upgrade(address _newAddress) public {
currentAddress = _newAddress;
}
function () payable external {
address implementaion = currentAddress;
require(currentAddress != address(0));
bytes memory data = msg.data;
assembly {
let result := delegatecall(gas, implementaion, add(data, 0x20), mload(data), 0, 0)
let size := returndatasize
let ptr := mload(0x40)
returndatacopy(ptr, 0, size)
switch result
case 0 {revert(ptr, size)}
default {return(ptr, size)}
}
}
}
const Dogs = artifacts.require("Dogs");
const Proxy = artifacts.require("Proxy");
module.exports = async function(deployer, network, accounts) {
const dogs = await Dogs.new();
const proxy = await Proxy.new(dogs.address);
}
It might not be an error from code. Have you tried restarting your machine?
1 Like
Hi @JohnVersus,
Or maybe because of this error of the fallback function?
Would ypu please advice how to resolve this error
Thanks in advance
Hi, Can you share the code here? I will test it on my end.
Hi, in the proxy contract.
The error says: (Expected a state variable declaration. If you intended this as a fallback function or a function to handle plain ether transactions, use the “fallback” keyword or the “receive” keyword instead.(2915)
Function: null
Contract: Proxy
function null()
payable external )
I’m using VS code and tried to deploy it in the terminal from VS code (command prompt.
// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;
import "./Storage.sol";
contract Proxy is Storage{
address currentAddress;
constructor(address _currentAddress) public{
currentAddress = _currentAddress;
}
function upgrade(address _newAddress) public {
currentAddress = _newAddress;
}
function () payable external {
address implementaion = currentAddress;
require(currentAddress != address(0));
bytes memory data = msg.data;
assembly {
let result := delegatecall(gas, implementaion, add(data, 0x20), mload(data), 0, 0)
let size := returndatasize
let ptr := mload(0x40)
returndatacopy(ptr, 0, size)
switch result
case 0 {revert(ptr, size)}
default {return(ptr, size)}
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;
contract Storage{
mapping(string => uint256) _uintStorage;
mapping(string => address) _addressStorage;
mapping(string => bool) _boolStorage;
mapping(string => string) _stringStorage;
mapping(string => bytes4) _bytesStorage;
address public owner;
bool public _initialized;
}`Preformatted text`
// SPDX-License-Identifier: MIT
pragma solidity >=0.4.22 <0.9.0;
import "./Storage.sol";
contract Dogs is Storage{
modifier onlyOnwer(){
require(msg.sender == owner);
_;
}
constructor () public{
owner == msg.sender;
}
function getNumberOfDogs() public view returns (uint256){
return _uintStorage["Dogs"];
}
function setNumberOfDogs(uint256 toSet) public{
_uintStorage["Dogs"] = toSet;
}
}
const Dogs = artifacts.require("Dogs");
const Proxy = artifacts.require("Proxy");
module.exports = async function(deployer, network, accounts) {
const dogs = await Dogs.new();
const proxy = await Proxy.new(dogs.address);
}
Replace this line with the below line. In the latest solidity versions function is not allowed without a name and it is replaced by a fallback keyword in the latest version.
fallback () payable external {
1 Like
Thanks @JohnVersus,
But in the assembly, the gas should be called
assembly {
let result := delegatecall(gas, implementaion, add(data, 0x20), mload(data), 0, 0)
let size := returndatasize
let ptr := mload(0x40)
returndatacopy(ptr, 0, size)
switch result
case 0 {revert(ptr, size)}
default {return(ptr, size)}
}
What do you think?
Yes, you can keep the remaining code as it is
fallback () payable external {
address implementaion = currentAddress;
require(currentAddress != address(0));
bytes memory data = msg.data;
assembly {
let result := delegatecall(gas(), implementaion, add(data, 0x20), mload(data), 0, 0)
let size := returndatasize()
let ptr := mload(0x40)
returndatacopy(ptr, 0, size)
switch result
case 0 {revert(ptr, size)}
default {return(ptr, size)}
}
}
1 Like
What is your compiler version as per truffle?
As per your proxy code your compiler version should be >=0.4.22 <0.9.0. Mismatch in the compiler version can also cause your error.
Can you please try with any compiler version greater than or equal to 0.6.2 .
It seems fallback was not present in the older version of solidity.
I can see the same error when I try with your solidity version.
1 Like
There is no issue with your code so it must be an error with the compiler.
Can you try with this command? It will remove previously compiled data and will compile it again.
truffle compile --reset --all
Unfortunately, the same issue persists.