StateVariables.sol

// SPDX-License-Identifier: MIT
pragma solidity 0.8.20;

import {Counter} from "./Counter.sol";

contract StateVariables {
    // uint256 empty, static, private, internal, public
    uint256 private staticPrivateNumber;
    uint256 internal staticInternalNumber;
    uint256 public staticPublicNumber;

    // uint256 non-empty, static, private, internal, public
    uint256 private staticNonEmptyPrivateNumber = 1;
    uint256 internal staticNonEmptyInternalNumber = 2;
    uint256 public staticNonEmptyPublicNumber = 3;

    // uint256 empty private, internal, public and altered in functions
    uint256 private emptyAlteredPrivateNumber;
    uint256 internal emptyAlteredInternalNumber;
    uint256 public emptyAlteredPublicNumber;

    // uint256 non-empty private, internal, public and altered in functions
    uint256 private nonEmptyAlteredPrivateNumber = 1;
    uint256 internal nonEmptyAlteredInternalNumber = 2;
    uint256 public nonEmptyAlteredPublicNumber = 3;

    // uint256 constant, private, internal, public
    uint256 private constant PRIVATE_CONSTANT = 1;
    uint256 internal constant INTERNAL_CONSTANT = 2;
    uint256 public constant PUBLIC_CONSTANT = 3;

    // uint256 immutable, private, internal, public
    uint256 private immutable privateImmutableNumber;
    uint256 internal immutable internalImmutableNumber;
    uint256 public immutable publicImmutableNumber;

    address public addr;

    constructor(uint256 _privateImmutableNumber, uint256 _internalImmutableNumber, uint256 _publicImmutableNumber) {
        privateImmutableNumber = _privateImmutableNumber;
        internalImmutableNumber = _internalImmutableNumber;
        publicImmutableNumber = _publicImmutableNumber;
    }

    error ZeroAddressError();

    function setAddrNoZeroError(address newAddr) public {
        if (newAddr == address(0)) revert ZeroAddressError();
        addr = newAddr;
    }

    function setAddrNoZeroRequire(address newAddr) public {
        require(newAddr != address(0), "Address cannot be zero");
        addr = newAddr;
    }

    function setAddrNoCheck(address newAddr) public {
        addr = newAddr;
    }

    function setEmptyAlteredNumbers(
        uint256 _emptyAlteredPrivateNumber,
        uint256 _emptyAlteredInternalNumber,
        uint256 _emptyAlteredPublicNumber
    ) public {
        emptyAlteredPrivateNumber = _emptyAlteredPrivateNumber;
        emptyAlteredInternalNumber = _emptyAlteredInternalNumber;
        emptyAlteredPublicNumber = _emptyAlteredPublicNumber;
    }

    function setNonEmptyAlteredNumbers(
        uint256 _nonEmptyAlteredPrivateNumber,
        uint256 _nonEmptyAlteredInternalNumber,
        uint256 _nonEmptyAlteredPublicNumber
    ) public {
        nonEmptyAlteredPrivateNumber = _nonEmptyAlteredPrivateNumber;
        nonEmptyAlteredInternalNumber = _nonEmptyAlteredInternalNumber;
        nonEmptyAlteredPublicNumber = _nonEmptyAlteredPublicNumber;
    }
}