= ActsAsPreviousNext

== Description

This 'acts_as' extension provides the capability for having previous & next methods for an object.
Previous & next are based on a specified column (default is id).

== Install

In your Gemfile

  gem 'acts_as_previous_next'

Currently is tested on rails3.2.0.rc2, ruby 1.9.3 and mysql

== Example

  class Post < ActiveRecord::Base
    acts_as_previous_next
    # acts_as_previous_next column: :id
    # or
    # acts_as_previous_next :id
  end

  post = Post.new
  post.next # => nil
  post.save
  post.next # => post
  post.previous # => post
  another_post = Post.new
  another_post.save
  another_post.next # => post
  another_post.previous # => post

Currently CanCan authorization is supported as option (+false+ by default). If cancan authorization is
enabled then +current_ability+ must be passed to next, previous methods. So the previous example
with cancan will be:

  class Post < ActiveRecord::Base
    acts_as_previous_next with_cancan: true

    belongs_to :user
  end

And in your view:

  link_to 'Next', @post.next(current_ability)
  link_to 'Previous', @post.previous(current_ability)