Comment by chalst

The code does not try to be clever:

    var getHeadings = function(table) {
      var firstRow = table.find("tr:first").first();
      return notNull(opts.headings) ? opts.headings : rowValues(firstRow);
    };

The code is also going to fall down if you have things like wide/high cells. But HTML tables are so flexible and so routinely abused, I guess the problem is too hard to be solved robustly with any generality.