"byte" casting function was removed since 0.8.0

[vijoin]

This line (see here) is throwing this error: ParserError: Expected primary expression when using the byte casting function

Look at The type byte has been removed. It was an alias of bytes1. in solidity changelog

How to replicate:

• try to compile with a version 0.8.0 or higher

I tested it with 0.7.6 and compilation passed (isolating the uint2str function)

Solution

use bytes1 instead