Build a decentralized app with Solidity (Quickstart)

VendingMachine.sol

1// SPDX-License-Identifier: MIT2pragma solidity ^0.8.9;3
4contract VendingMachine {5   mapping(address => uint) private _cupcakeBalances;6   mapping(address => uint) private _cupcakeDistributionTimes;7
8   function giveCupcakeTo(address userAddress) public returns (bool) {9       if (_cupcakeDistributionTimes[userAddress] == 0) {10           _cupcakeBalances[userAddress] = 0;11           _cupcakeDistributionTimes[userAddress] = 0;12       }13
14       uint fiveSecondsFromLastDistribution = _cupcakeDistributionTimes[userAddress] + 5 seconds;15       bool userCanReceiveCupcake = fiveSecondsFromLastDistribution <= block.timestamp;16
17       if (userCanReceiveCupcake) {18           _cupcakeBalances[userAddress]++;19           _cupcakeDistributionTimes[userAddress] = block.timestamp;20           return true;21       } else {22           revert("HTTP 429: Too Many Cupcakes (you must wait at least 5 seconds between cupcakes)");23       }24   }25
26   function getCupcakeBalanceFor(address userAddress) public view returns (uint) {27       return _cupcakeBalances[userAddress];28   }29}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

contract VendingMachine {
   mapping(address => uint) private _cupcakeBalances;
   mapping(address => uint) private _cupcakeDistributionTimes;

function giveCupcakeTo(address userAddress) public returns (bool) {
       if (_cupcakeDistributionTimes[userAddress] == 0) {
           _cupcakeBalances[userAddress] = 0;
           _cupcakeDistributionTimes[userAddress] = 0;
       }

uint fiveSecondsFromLastDistribution = _cupcakeDistributionTimes[userAddress] + 5 seconds;
       bool userCanReceiveCupcake = fiveSecondsFromLastDistribution <= block.timestamp;

if (userCanReceiveCupcake) {
           _cupcakeBalances[userAddress]++;
           _cupcakeDistributionTimes[userAddress] = block.timestamp;
           return true;
       } else {
           revert("HTTP 429: Too Many Cupcakes (you must wait at least 5 seconds between cupcakes)");
       }
   }

function getCupcakeBalanceFor(address userAddress) public view returns (uint) {
       return _cupcakeBalances[userAddress];
   }
}

Console1 events

[lab]Loaded VendingMachine.sol; compiler target solc 0.8.34.

Ln 1, Col 129 lines · Solidity · 0.8.34