combine

  def combine(refs)
    combined = refs.first
    refs[1..-1].each do |ref|
      if combined.index(ref.gsub(/\:.*$/, '')) == 0
        combined += ',' + /\:(.*)$/.match(ref)[1]
      elsif combined.index(ref.gsub(/\d+\:.*$/, '')) == 0
        combined += ';' + /\d+\:.*$/.match(ref)[0]
      else
        return nil
      end
    end
    combined
  end

 

 具体示例：

 

    puts combine(["3:23", "3:24", "4:1"])  # => 3:23,24;4:1