dir ( ';' FILE )*

Macro

public String _dir(String[] args) {
    if (args.length < 2) {
        reporter.warning("Need at least one file name for ${dir;...}");
        return null;
    }
    String result = Arrays.stream(args, 1, args.length)
        .map(domain::getFile)
        .filter(File::exists)
        .map(File::getParentFile)
        .filter(File::exists)
        .map(IO::absolutePath)
        .collect(Strings.joining());
    return result;
}