Safety · easy

10. require & revert

Guard your functions.

Add `onlyPositive(int256 x)` that `require(x > 0, "must be positive")` and returns `uint256(x)`.

Required in your answer: require(x > 0must be positiveuint256(x)

Compiles with solc in your browser

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

contract Guard {
    function onlyPositive(int256 x) external pure returns (uint256) {
        // TODO require + cast
    }
}

Output appears here.

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