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# nlohmann::basic_json::default_object_comparator_t

    using default_object_comparator_t = std::less<StringType>;  // until C++14

    using default_object_comparator_t = std::less<>;            // since C++14

The default comparator used by `object_t`.

Since C++14 a transparent comparator is used which prevents unnecessary string construction when looking up a key in an object.

The actual comparator used depends on `object_t` and can be obtained via `object_comparator_t`.

## Examples

Example

The example below demonstrates the default comparator.

    #include <iostream>
    #include <nlohmann/json.hpp>

    using json = nlohmann::json;

    int main()
    {
        std::cout << std::boolalpha
                  << "one < two : " << json::default_object_comparator_t{}("one", "two") << "\n"
                  << "three < four : " << json::default_object_comparator_t{}("three", "four") << std::endl;
    }

Output:

    one < two : true
    three < four : false

## Version history

- Added in version 3.11.0.

Last update: May 17, 2022
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