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# nlohmann::basic_json::array_t
```
using array_t = ArrayType<basic_json, AllocatorType<basic_json>>;
```
The type used to store JSON arrays.
[RFC 8259](https://tools.ietf.org/html/rfc8259) describes JSON arrays as follows:
> An array is an ordered sequence of zero or more values.
To store objects in C++, a type is defined by the template parameters explained below.
## Template parameters
`ArrayType` : container type to store arrays (e.g., `std::vector` or `std::list`)
`AllocatorType` : the allocator to use for objects (e.g., `std::allocator`)
## Notes
#### Default type
With the default values for `ArrayType` (`std::vector`) and `AllocatorType` (`std::allocator`), the default value for `array_t` is:
```
std::vector<
basic_json, // value_type
std::allocator<basic_json> // allocator_type
>
```
#### Limits
[RFC 8259](https://tools.ietf.org/html/rfc8259) specifies:
> An implementation may set limits on the maximum depth of nesting.
In this class, the array's limit of nesting is not explicitly constrained. However, a maximum depth of nesting may be introduced by the compiler or runtime environment. A theoretical limit can be queried by calling the [`max_size`](https://json.nlohmann.me/api/basic_json/max_size/index.md) function of a JSON array.
#### Storage
Arrays are stored as pointers in a `basic_json` type. That is, for any access to array values, a pointer of type `array_t*` must be dereferenced.
## Examples
Example
The following code shows that `array_t` is by default, a typedef to `std::vector<nlohmann::json>`.
```
#include <iostream>
#include <iomanip>
#include <nlohmann/json.hpp>
using json = nlohmann::json;
int main()
{
std::cout << std::boolalpha << std::is_same<std::vector<json>, json::array_t>::value << std::endl;
}
```
Output:
```
true
```
## Version history
- Added in version 1.0.0.