Niels Lohmann 29cd970b94
Consolidate documentation (#3071)
* 🔥 consolidate documentation
* ♻️ overwork std specializations
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* 📝 add note for https://github.com/nlohmann/json/issues/874#issuecomment-1001699139
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2021-12-29 13:41:01 +01:00

1.1 KiB

nlohmann::basic_json::flatten

basic_json flatten() const;

The function creates a JSON object whose keys are JSON pointers (see RFC 6901) and whose values are all primitive (see is_primitive() for more information). The original JSON value can be restored using the unflatten() function.

Return value

an object that maps JSON pointers to primitive values

Exception safety

Strong exception safety: if an exception occurs, the original value stays intact.

Complexity

Linear in the size the JSON value.

Notes

Empty objects and arrays are flattened to #!json null and will not be reconstructed correctly by the unflatten() function.

Examples

??? example

The following code shows how a JSON object is flattened to an object whose keys consist of JSON pointers.

```cpp
--8<-- "examples/flatten.cpp"
```

Output:

```json
--8<-- "examples/flatten.output"
```

See also

Version history

  • Added in version 2.0.0.