normalize_mailaddress_list.rb

#!/usr/bin/env ruby

pattern = /^(?:(?:(?:(?:[a-zA-Z0-9_!#\$\%&'*+\/=?\^`{}~|\-]+)(?:\.(?:[a-zA-Z0-9_!#\$\%&'*+\/=?\^`{}~|\-]+))*)|(?:"(?:\\[^\r\n]|[^\\"])*")))\@(?:(?:(?:(?:[a-zA-Z0-9_!#\$\%&'*+\/=?\^`{}~|\-]+)(?:\.(?:[a-zA-Z0-9_!#\$\%&'*+\/=?\^`{}~|\-]+))*)|(?:\[(?:\\\S|[\x21-\x5a\x5e-\x7e])*\])))$/

table = {}

open(ARGV.shift) do |fd|
  fd.each do |line|
    date, mail = line.split(/,/)
    table[mail] = date if mail =~ pattern
  end
end

puts table.keys.map{|mail|
  "#{table[mail]},#{mail}"
}.sort.join("")