Project comparisons allow you to view any selection of projects side by side just like they're shown on regular categories or in search results. You can try out an example or start yourself by adding a library to the comparison via the input below. You can also easily share your current comparison with others by sending the URL of the current page.
This is just an extraction from Ransack/Squeel. You probably don't want to use this directly. It extends ActiveRecord's associations to support polymorphic belongs_to associations.