Solidity: View and Pure Functions

Getter functions can be declared view or pure.

View function declares that no state will be changed.

Pure function declares that no state variable will be changed or read.

// SPDX-License-Identifier: MIT
pragma solidity ^0.7.3;

contract ViewAndPure {
    uint public x = 1;

    // Promise not to modify the state.
    function addToX(uint y) public view returns (uint) {
        return x + y;
    }

    // Promise not to modify or read from the state.
    function add(uint i, uint j) public pure returns (uint) {
        return i + j;
    }
}