Move files

#!/use/bin/ruby
# coding: utf-8
require 'fileutils'
require 'pathname'
abort unless ARGV.size == 1
base_dir = Pathname ARGV.shift
base_dir.children.each do |f|
  dir = Pathname "#{base_dir}/#{f.mtime.strftime '%Y年%m月%d日'}"
  FileUtils::Verbose.mkdir dir unless dir.directory?
  FileUtils::Verbose.mv f, dir
end