Solution to http://codekata.com/kata/kata06-anagrams/

anagrams.rb

require 'set'

class AnagramDict
  include Enumerable

  def initialize
    @dict = {}
  end

  def put(word)
    (@dict[key word] ||= Set[]) << word
  end

  def set_count
    @dict.count
  end

  def each(&blk)
    @dict.each(&blk)
  end

  private
  def key(word)
    word.chars.sort.join
  end
end

anagrams = AnagramDict.new
File.open('./wordlist.txt').each do |line|
  anagrams.put(line.chomp)
end

puts "Sets: #{anagrams.set_count}"

most_similar =
  anagrams.max_by { |(_, words)| words.count }.last

puts "Largest set: #{most_similar.to_a.join(' ')}"

longest =
  anagrams
    .select { |(_, words)| words.count > 2 }
    .max_by { |(key, _)| key.length }.last

puts "Longest anagram: #{longest.to_a.join(' ')}"