template<typenameU,typenameV,typename...Args> class ObjectType = std::map,
template<typenameU,typename...Args> class ArrayType = std::vector,
class StringType = std::string,
class BooleanType = bool,
class NumberIntegerType = int64_t,
class NumberFloatType = double,
template<typenameU> class Allocator = std::allocator
> class basic_json;
```
## Template Parameters
-`ObjectType` - The type to store collection of name/value pairs. It can be any associative container that can hold key-value pairs as long as the key type is the same as `StringType`. The value type is again `nlohmann::basic_json`. The parameter `ObjectType` defaults to [`std::map`](http://en.cppreference.com/w/cpp/container/map).
-`ArrayType` - The type to store ordered value lists. It can be any sequence container. The parameter `ArrayType` defaults to a [`std::vector`](http://en.cppreference.com/w/cpp/container/vector) whose elements are of type `nlohmann::basic_json`.
-`StringType` - The type to store string values. The parameter `StringType` defaults to [`std::string`](http://en.cppreference.com/w/cpp/string/basic_string).
-`BooleanType`
-`NumberIntegerType`
-`NumberFloatType`
-`Allocator` - An allocator that is used to acquire memory to store the elements. The type must meet the requirements of [`Allocator`](http://en.cppreference.com/w/cpp/concept/Allocator).
## Specializations
A standard JSON type `nlohmann::json` is defined in `<json.hpp>` which uses the default types:
