# code: http://golf.shinh.org/reveal.rb?Convert+hex+to+decimal/tails_1645184237&nbb
# target Nibbles version: 0.23
# commenter version: 0.1.2.181

hex #(to/from hex):int 
    | #(filter):[chr] 
        fstLine #(@):[chr] 
        \A 
        \ #(char class):[chr] 
            A #($):chr 
            n #(isAlphaNum):null