Ruby method to remove accents from UTF-8 international characters

Gus Shortz picture Gus Shortz · Mar 28, 2013 · Viewed 29.7k times · Source

I am trying to create a 'normalized' copy of a string, to help reduce duplicate names in a database. The names contain many international characters (ie. accented letters), and I want to create a copy with the accents removed.

I did come across the method below, but cannot get it to work. I can't seem to find what the Unicode Hacks plugin is.

  # Utility method that retursn an ASCIIfied, downcased, and sanitized string.
  # It relies on the Unicode Hacks plugin by means of String#chars. We assume
  # $KCODE is 'u' in environment.rb. By now we support a wide range of latin
  # accented letters, based on the Unicode Character Palette bundled inMacs.
  def self.normalize(str)
     n = str.chars.downcase.strip.to_s
     n.gsub!(/[à áâãäåÄÄ?]/u,    'a')
     n.gsub!(/æ/u,                  'ae')
     n.gsub!(/[ÄÄ?]/u,                'd')
     n.gsub!(/[çÄ?ÄÄ?Ä?]/u,          'c')
     n.gsub!(/[èéêëÄ?Ä?Ä?Ä?Ä?]/u, 'e')
     n.gsub!(/Æ?/u,                   'f')
     n.gsub!(/[ÄÄ?Ä¡Ä£]/u,            'g')
     n.gsub!(/[ĥħ]/,                'h')
     n.gsub!(/[ììíîïīĩĭ]/u,     'i')
     n.gsub!(/[įıijĵ]/u,           'j')
     n.gsub!(/[ķĸ]/u,               'k')
     n.gsub!(/[Å?ľĺļÅ?]/u,         'l')
     n.gsub!(/[ñÅ?Å?Å?Å?Å?]/u,       'n')
     n.gsub!(/[òóôõöøÅÅ?ÅÅ]/u,  'o')
     n.gsub!(/Å?/u,                  'oe')
     n.gsub!(/Ä?/u,                   'q')
     n.gsub!(/[Å?Å?Å?]/u,             'r')
     n.gsub!(/[Å?Å¡Å?ÅÈ?]/u,          's')
     n.gsub!(/[ťţŧÈ?]/u,           't')
     n.gsub!(/[ùúûüūůűŭũų]/u,'u')
     n.gsub!(/ŵ/u,                   'w')
     n.gsub!(/[ýÿŷ]/u,             'y')
     n.gsub!(/[žżź]/u,             'z')
     n.gsub!(/\s+/,                   ' ')
     n.gsub!(/[^\sa-z0-9_-]/,          '')
     n
  end

Do I need to 'require' a particular library/gem? Or maybe someone could recommend another way to go about this.

I am not using Rails, nor do I plan on doing so.

Answer

user2398029 picture user2398029 · Mar 29, 2013

I generally use I18n to handle this:

1.9.3p392 :001 > require "i18n"
 => true
1.9.3p392 :002 > I18n.transliterate("Hé les mecs!")
 => "He les mecs!"