get_and_create()

template<typename BasicJsonType >

BasicJsonType & nlohmann::json_pointer< BasicJsonType >::get_and_create ( BasicJsonType &  j ) const

inlineprivate

create and return a reference to the pointed to value

@complexity Linear in the number of reference tokens.

Exceptions

parse_error.109	if array index is not a number
type_error.313	if value cannot be unflattened

Definition at line 12943 of file json.hpp.

    {
        auto *result = &j;
 
        // in case no reference tokens exist, return a reference to the JSON value
        // j which will be overwritten by a primitive value
        for (const auto &reference_token : reference_tokens)
        {
            switch (result->type())
            {
                case detail::value_t::null:
                {
                    if (reference_token == "0")
                    {
                        // start a new array if reference token is 0
                        result = &result->operator[](0);
                    }
 
                    else
                    {
                        // start a new object otherwise
                        result = &result->operator[](reference_token);
                    }
 
                    break;
                }
 
                case detail::value_t::object:
                {
                    // create an entry in the object
                    result = &result->operator[](reference_token);
                    break;
                }
 
                case detail::value_t::array:
                {
                    // create an entry in the array
                    result = &result->operator[](array_index(reference_token));
                    break;
                }
 
                /*
                The following code is only reached if there exists a reference
                token _and_ the current value is primitive. In this case, we have
                an error situation, because primitive values may only occur as
                single value; that is, with an empty list of reference tokens.
                */
                case detail::value_t::string:
                case detail::value_t::boolean:
                case detail::value_t::number_integer:
                case detail::value_t::number_unsigned:
                case detail::value_t::number_float:
                case detail::value_t::binary:
                case detail::value_t::discarded:
                default:
                    JSON_THROW(detail::type_error::create(313, "invalid value to unflatten", j));
            }
        }
 
        return *result;
    }