def normalize(str, form=ActiveSupport::Multibyte::DEFAULT_NORMALIZATION_FORM)
codepoints = u_unpack(str)
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