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### jsoncons::basic_json::try_emplace
```cpp
template <typename T>
pair<object_iterator, bool> try_emplace(const string_view_type& key,
Args&&... args); (1)
template <typename T>
object_iterator try_emplace(const_object_iterator hint,
const string_view_type& key,
Args&&... args); (2)
```
#### Parameters
key
The key used both to look up and to insert if not found
hint
Iterator to the position before which the new element will be inserted
args
Arguments to forward to the constructor of the element
#### Return value
(1) returns a pair consisting of first, an iterator to the inserted value
or the already existing value,
and second, a bool indicating whether the insertion took place
(true for insertion, false for no insertion.)
(2) returns an iterator to the inserted value
or the already existing value.
#### Exceptions
Throws `std::domain_error` if not a json object.
### Example
```cpp
json a;
a.try_emplace("object1",json());
a.try_emplace("field1","value1");
a["object1"].try_emplace("field2","value2");
std::cout << a << '\n';
```
Output:
```json
{"field1":"value1","object1":{"field2":"value2"}}
```
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