can't load require_dependency

问题

I'm trying to use require_dependency from ActiveSupport library in pry:

require 'active_support'  #=> true
require_dependency 'test' #=> NoMethodError: undefined method  
                          #=> `require_dependency' for main:Object

What could be the problem?

回答1:

ActiveSupport used to be pretty evil by loading a ton of stuff on require. The "kitchen sink" approach opened a lot of core classes up and changed their behavior (like JSON). This caused incompatibilities/problems with other gems and code that expected core ruby functions to behave like their vanilla selves.

So now requiring just active_support does not load anything.

see http://edgeguides.rubyonrails.org/active_support_core_extensions.html

in your case you probably will need require 'active_support/core_ext'

来源：https://stackoverflow.com/questions/11021955/cant-load-require-dependency