Cicu

Custom ICU rulesets for collation in ruby - requires libicu

Make sure libicu is installed:

$ sudo apt-get install libicu-dev

Add this line to your application's Gemfile:

gem 'cicu'

And then execute:

$ bundle

Or install it yourself as:

$ gem install cicu

Create a ruleset

ruleset = Cicu::Ruleset.new("[normalization on] & b < a < c")

Sort an array

ary = %w( a b c ba bb bc )
sorted_ary = ruleset.sort_by { |el| ruleset.sort_key(el) }
# => "["b", "bb", "ba", "bc", "a", "c"]"

Get the sort key for a string

ruleset.sort_key("abc")
# => "*\x04)*\x05\x01\a\x01\a"

You can store sort keys in a database column to use them in ORDER BY queries. Make sure to use a column type that supports binary strings (e.g. MySQLs VARBINARY).

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request