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Solidity by Example
version 0.8.3

dark mode

Immutable

Immutable variables are like constants. Values of immutable variables can be set inside the constructor but cannot be modified afterwards.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.3;

contract Immutable {
    // coding convention to uppercase constant variables
    address public immutable MY_ADDRESS;
    uint public immutable MY_UINT;

    constructor(uint _myUint) {
        MY_ADDRESS = msg.sender;
        MY_UINT = _myUint;
    }
}

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