nlohmann::ordered_json_document¶
Defined in header <nlohmann/json_view.hpp>
using ordered_json_document = basic_json_document<ordered_json, view_mode::read_only>;
This type is a basic_json_document of the ordered_json specialization: materialize() on one of its views preserves the insertion order of object keys, instead of sorting them like json_document does.
Examples¶
Example
The example below demonstrates how ordered_json_document preserves the insertion order of object keys when materializing.
#include <iostream>
#include <nlohmann/json_view.hpp>
using nlohmann::ordered_json_document;
int main()
{
// ordered_json_document is basic_json_document<nlohmann::ordered_json>:
// materialize() preserves the insertion (source) order of object keys,
// instead of sorting them like json_document does
ordered_json_document doc = ordered_json_document::parse(R"({"z": 1, "a": 2, "m": 3})");
std::cout << doc.root().materialize().dump() << '\n';
}
Output:
{"z":1,"a":2,"m":3}
See also¶
ordered_json_view- a view of a value of anordered_json_documentjson_document- the corresponding document for the defaultjsonspecialization- Object Order - preserving the insertion order of object keys
- Zero-copy JSON views - how to parse, inspect and edit a document without building a tree
Version history¶
Added in version 3.13.0 unreleased.