class Struct

{"json_class":"Struct","t":{'name':'Rowdy',"age":null}}

Output:

puts Struct::Customer.new.to_json
Customer = Struct.new('Customer', :name, :address, :zip)
require 'json/add/struct'

Returns a JSON string representing +self+:

def to_json(*args)
  as_json.to_json(*args)
end