LCCLasses

A Ruby gem that provides the Library of Congress Classification system main classes and subclasses along with some convenience methods.

LCCLasses is available on RubyGems:

gem install lcclasses

To install with Bundler, add the following to your Gemfile:

gem 'lcclasses'

Then run bundle install

To find a classification code:

LCClasses.find_main_class_by_code("T")
=> ["T", "Technology (General)"]
LCClasses.find_subclass_by_code("AM")
=> ["AM", "Museums. Collectors and collecting"]
LCClasses.find_all_by_code("E")
=> # returns the main "E" class and all subclasses in nested array
LCClasses.main_classes
=> # returns all main classes
LCClasses.subclasses
=> # returns all subclasses

The entire set of classes can be retrieved in 3 formats:

LCClasses::CLASS_HASH
=> # nested hash of classes and subclasses
LCClasses.nested
=> # nested array of classes and subclasses as LCClasses::LCClass objects
LCClasses.flat
=> # flat array of classes and subclasses as LCClasses::LCClass objects

The CLASS_HASH constant is in the following format (truncated example):

{ "A" => {
    :name => "General Works",
    :subclasses => {
      "AC" => { :name => "Collections; Series; Collected works" }
    }
  }
}

Classes are returned as specialized LCClasses::Class arrays in the format [code, name]. In the case of nested LCClasses:LCClass objects, they are in the format [main_class_code, main_class_name, [[subclass_code, subclass_name]]]. These objects are normal arrays with the following methods added:

@class = LCClasses.find_main_class_by_code("M")
@class.code
=> "M"
@class.name
=> "Music"
@class.subclasses
=> [["M", "Music"], ["ML", "Literature on music"], ["MT", "Instruction and study"]]

• Fork the project.
• Make your feature addition or bug fix.
• Add tests for it. This is important so I don't break it in a future version unintentionally.
• Commit, do not mess with rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
• Send me a pull request. Bonus points for topic branches.

Copyright (c) 2010 William Melody. See LICENSE for details.