class Asciidoctor::Table

def create_columns colspecs
  cols = []
  autowidth_cols = nil
  width_base = 0
  colspecs.each do |colspec|
    colwidth = colspec['width']
    cols << (Column.new self, cols.size, colspec)
    if colwidth < 0
      (autowidth_cols ||= []) << cols[-1]
    else
      width_base += colwidth
    end
  end
  if (num_cols = (@columns = cols).size) > 0
    @attributes['colcount'] = num_cols
    width_base = nil unless width_base > 0 || autowidth_cols
    assign_column_widths width_base, autowidth_cols
  end
  nil
end