Counters before or after constructor

Smart Contracts
1

Why is the counter initialized before the constructor? Does it matter? Can I put other variables above the constructor? Could I put the counter variables below the constructor?

"""

// SPDX-License-Identifier: MIT pragma solidity ^0.8.4; 
import "[@openzeppelin/contracts/token/ERC721/ERC721.sol](https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v4.7.3/contracts/token/ERC721/ERC721.sol)"; 
import "[@openzeppelin/contracts/access/Ownable.sol](https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v4.7.3/contracts/access/Ownable.sol)"; 
import "[@openzeppelin/contracts/utils/Counters.sol](https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v4.7.3/contracts/utils/Counters.sol)"; 
contract MyToken is ERC721, Ownable { using Counters for Counters.Counter; 

Counters.Counter private _tokenIdCounter; 

constructor() ERC721("MyToken", "MTK") {} 

function safeMint(address to) public onlyOwner { 
uint256 tokenId = _tokenIdCounter.current(); 
_tokenIdCounter.increment(); 
_safeMint(to, tokenId); } }

"""

2

Please use triple backticks to surround your code in order to get proper formatting.

```
code here
```

You can put the variable before or after the constructor. The convention is to put it before.

1 Like
3

Thanks for the answer and thanks for the tip about the code. That's way better.