methods-collect.rb

# >http://d.hatena.ne.jp/kenkitii/20090204/ruby_levenshtein_distance>
def levenshtein_distance(str1, str2)
  col, row = str1.size + 1, str2.size + 1
  d = row.times.inject([]){|a, i| a << [0] * col }
  col.times {|i| d[0][i] = i }
  row.times {|i| d[i][0] = i }

  str1.size.times do |i1|
    str2.size.times do |i2|
      cost = str1[i1] == str2[i2] ? 0 : 1
      x, y = i1 + 1, i2 + 1
      d[y][x] = [d[y][x-1]+1, d[y-1][x]+1, d[y-1][x-1]+cost].min
    end
  end
  d[str2.size][str1.size]
end
# <<

def method_missing(name, *args)
  s = methods.min_by {|s| levenshtein_distance name.to_s, s }
  puts "Did you mean this? #{s}"
end