class ActiveSupport::Deprecation::DeprecatedConstantProxy

Default deprecator is ActiveSupport::Deprecation.
deprecator_instance.
When someone use old constant this will trigger warn method on
OLD_CONST = ActiveSupport::Deprecation::DeprecatedConstantProxy.new(‘OLD_CONST’, ‘NEW_CONST’, deprecator_instance)
OLD_CONST = ActiveSupport::Deprecation::DeprecatedConstantProxy.new(‘OLD_CONST’, ‘NEW_CONST’)
This DeprecatedConstantProxy transforms constant to deprecated constant.

def class 

def class
  target.class
end

def initialize(old_const, new_const, deprecator = ActiveSupport::Deprecation.instance) 

def initialize(old_const, new_const, deprecator = ActiveSupport::Deprecation.instance)
  @old_const = old_const
  @new_const = new_const
  @deprecator = deprecator
end

def target 

def target
  ActiveSupport::Inflector.constantize(@new_const.to_s)
end

def warn(callstack, called, args) 

def warn(callstack, called, args)
  @deprecator.warn("#{@old_const} is deprecated! Use #{@new_const} instead.", callstack)
end