constexpr bool is_structured() const noexcept;
This function returns #!cpp true if and only if the JSON type is structured (array or object).
#!cpp true if type is structured (array or object), #!cpp false otherwise.
No-throw guarantee: this member function never throws exceptions.
Constant.
The term structured stems from RFC 8259:
JSON can represent four primitive types (strings, numbers, booleans, and null) and two structured types (objects and arrays).
Note that though strings are containers in C++, they are treated as primitive values in JSON.
??? example
The following code exemplifies `is_structured()` for all JSON types. ```cpp --8<-- "examples/is_structured.cpp" ``` Output: ```json --8<-- "examples/is_structured.output" ```