D: how to remove last char in string?

I need to remove last char in string in my case it's comma (","):

    foreach(line; fcontent.splitLines)
    {
        string row = line.split.map!(a=>format("'%s', ", a)).join;
        writeln(row.chop.chop);
    }

I have found only one way - to call chop two times. First remove \r\n and second remove last char.

Is there any better ways?