p6.p6

        nqp::if(
          $nofile,
          nqp::stmts(
            # This NQP chunklet does:
            #      /^ (<$volume_rx>?) (.*) /; (~$0, ~$1, '')
            #
            # The $vol-pos is the position in the $path where volume ends and
            # rest of the path begins. We search the string for a drive letter,
            # If we find it, then the we'll cut the $path at pos 2. If we don't,
            # Search for a UNC path. We check if the $path starts with two
            # slash/backslash chars. Then, we check the char after them is NOT
            # a slash/backslash. Then we look for index of '/' and index of '\'
            # and use the smaller index of the two. Now, all we do is search for
            # index of '/' and index '\': if we find neither, our whole $path
            # is the volume, otherwise use the smallest value as the cut point
            # for the path. Lastly, we we found neither the drive letter nor
            # the UNC path, then just return the $path as the dirname and use
            # empty string for the volume. Simple!
            nqp::if(
              (nqp::eqat($path, ':', 1) # /^ <[A..Z a..z]> ':'/
                && ( (nqp::isge_i(($_ := nqp::ord($path)), 65) # drive letter
                    && nqp::isle_i($_, 90))
                  || (nqp::isge_i($_, 97) && nqp::isle_i($_, 122)))),
              ($vol-pos = 2)),
            nqp::if(
              (nqp::iseq_i(($_ := nqp::ord($path)), 92), # /^<[\\/]>
                || nqp::iseq_i($_, 47))
              && (nqp::iseq_i(($_ := nqp::ord($path, 1)), 92), # /^.<[\\/]>
                || nqp::iseq_i($_, 47))
              && (nqp::isne_i(($_ := nqp::ord($path, 2)), 92), # /^..<-[\\/]>
                || nqp::isne_i($_, 47))
              && nqp::stmts( # find position of first slash/backlash
                (            $_ := nqp::index($path, '/', 3)),
                (my int $slash1  = nqp::index($path, ｢\｣, 3)),
                nqp::if( # if we found both types of slashes, use the first one
                  nqp::islt_i($_, $slash1) && nqp::isne_i($_, -1),
                  ($slash1 = $_)),
                nqp::isne_i($slash1, -1)) # did find find any slashes?
              && nqp::stmts( # find position of next slash/backlash
                ($slash1 = nqp::add_i($slash1, 1)), # bump to next pos
                (            $_ := nqp::index($path, '/', $slash1)),
                (my int $slash2  = nqp::index($path, ｢\｣, $slash1)),
                nqp::if( # if we found both types of slashes, use the first one
                  nqp::islt_i($_, $slash1) && nqp::isne_i($_, -1),
                  ($slash2 = $_)),
                nqp::if( # if slash2 is after slash1, this isn't UNC path
                  nqp::iseq_i($slash2, $slash1),
                  0, # give False to our conditional
                  nqp::if( # if didn't find slashes, use str end as vol-pos
                    nqp::iseq_i($slash1, -1),
                    ($slash1 = nqp::chars($path))))), # else, use $slash2 pos
              ($vol-pos = $slash2)),
            ( # return the...
                nqp::substr($path, 0, $vol-pos),  # volume...
                nqp::substr($path,    $vol-pos),  # dirs...
                '',                               # file
            ),
          ))