gistfile1.txt

    /** Return an @ref array pointer if this is an array, else return `nullptr`

        If `this->kind() == kind::array`, then a pointer
        to the underlying array is returned. Otherwise,
        `nullptr` is returned.

        @par Example

        The semantics of the function allow the return
        value to be used in a conditional expression as
        a boolean, or in a conditional assignment such
        as:
        @code
        if( auto p = jv.is_array() )
            ...
        @endcode

        @par Complexity
        Constant.

        @par Exception Safety
        No-throw guarantee.
    */
    array const*
    is_array() const noexcept