module ActiveSupport::Multibyte::Unicode

def normalize(string, form=nil)

ActiveSupport::Multibyte.default_normalization_form
:c, :kc, :d, or :kd. Default is
* form - The form you want to normalize in. Should be one of the following:
* string - The string to perform normalization on.

passing strings to databases and validations.
Returns the KC normalization of the string by default. NFKC is considered the best normalization form for 
def normalize(string, form=nil)
  form ||= @default_normalization_form
  # See http://www.unicode.org/reports/tr15, Table 1
  codepoints = u_unpack(string)
  case form
    when :d
      reorder_characters(decompose_codepoints(:canonical, codepoints))
    when :c
      compose_codepoints(reorder_characters(decompose_codepoints(:canonical, codepoints)))
    when :kd
      reorder_characters(decompose_codepoints(:compatability, codepoints))
    when :kc
      compose_codepoints(reorder_characters(decompose_codepoints(:compatability, codepoints)))
    else
      raise ArgumentError, "#{form} is not a valid normalization variant", caller
  end.pack('U*')
end