class ActionView::Helpers::JavaScriptVariableProxy

:nodoc:

def append_to_function_chain!(call) 

def append_to_function_chain!(call)
  @generator << @variable if @empty
  @empty = false
  super
end

def as_json(options = nil) 

def as_json(options = nil)
  @variable
end

def initialize(generator, variable)

:nodoc: 
def initialize(generator, variable)
  @variable = ::ActiveSupport::JSON::Variable.new(variable)
  @empty    = true # only record lines if we have to.  gets rid of unnecessary linebreaks
  super(generator)
end

def respond_to?(*)

Since it's a blank slate object, I suppose it responds to anything.
The JSON Encoder calls this to check for the +to_json+ method 
def respond_to?(*)
  true
end