Hashの配列を表にする

うまい書き方ができない…orz

ソース

#!/usr/local/bin/ruby
class TableWriter

  def initialize(rows)

    return if rows.size < 1

    @rows = rows

    set_names

    set_sizes

  end
  def to_s

    return "Empty set" unless @rows

    buf = ""

    puts_line(buf)

    puts_names(buf)

    puts_line(buf)

    @rows.each {|row| puts_row(row, buf)}

    puts_line(buf)

    return buf

  end
  private

  def set_names

    @names = @rows.first.keys

  end
  def set_sizes

    @sizes = {}

    @names.each {|name| @sizes[name] = name.size}

    @rows.each {|row|

      row.each {|name, val|

        size = val.to_s.size

        @sizes[name] = size if @sizes[name] < size

      }

    }

  end
  def rpad(str, len)

    return str + " " * (len - str.length)

  end
  def puts_names(buf)

    append_row(@names.collect {|name| rpad(name, @sizes[name])}, buf)

  end
  def puts_row(row, buf)

    append_row(@names.collect {|name| rpad(row[name].to_s, @sizes[name])}, buf)

  end
  def puts_line(buf)

    append_row(@names.collect {|title| "-" * @sizes[title]}, buf, "+")

  end
  def append_row(ary, buf, sep="|")

    buf << sep + ary.join(sep) + sep  + "\n"

  end

end
rows = []

rows << {"ID"=>"001", "NAME"=>"Yamada Taro",    "AGE"=>21}

rows << {"ID"=>"002", "NAME"=>"山田花子",       "AGE"=>18}

rows << {"ID"=>"003", "NAME"=>"Suszuki Ichiro", "AGE"=>28}
puts TableWriter.new(rows)

実行結果

~/work$ ./table.rb
+--------------+---+---+
|NAME          |ID |AGE|
+--------------+---+---+
|Yamada Taro   |001|21 |
|山田花子      |002|18 |
|Suszuki Ichiro|003|28 |
+--------------+---+---+