Solidity byte <--> uint8

gistfile1.txt

pragma solidity ^0.5.1;

contract Test {
  
    function getRand() view public returns (uint8, uint8, uint8, uint8) {
        uint256 t = rand;
        bytes memory bb = toBytes(t);
        return (toUnit(bb[7]), toUnit(bb[15]), toUnit(bb[23]), toUnit(bb[31]));
    }
    
    function toBytes(uint256 x) private pure returns (bytes memory b) {
        b = new bytes(32);
        assembly { mstore(add(b, 32), x) }
    }
    
    function toUnit(byte t) private pure returns (uint8) {
        return uint8(t);
    }
}