Been playing with Ruby on Rails for awhile and decided to take a look through the actual source. Grabbed the repo from GitHub and started looking around. Came across some code that I am not sure what it does or what it references.
I saw this code in actionmailer/test/abstract_unit.rb
root = File.expand_path('../../..', __FILE__) begin require "#{root}/vendor/gems/environment" rescue LoadError $:.unshift("#{root}/activesupport/lib") $:.unshift("#{root}/actionpack/lib")endlib = File.expand_path("#{File.dirname(__FILE__)}/../lib")$:.unshift(lib) unless $:.include?('lib') || $:.include?(lib)require 'rubygems'require 'test/unit'require 'action_mailer'require 'action_mailer/test_case'Can someone tell me what the $: (a.k.a. "the bling") is referencing?
