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# nlohmann::byte_container_with_subtype::clear_subtype

    void clear_subtype() noexcept;

Clears the binary subtype and flags the value as not having a subtype, which has implications for serialization; for instance MessagePack will prefer the bin family over the ext family.

## Exception safety

No-throw guarantee: this function never throws exceptions.

## Complexity

Constant.

## Examples

Example

The example below demonstrates how `clear_subtype` can remove subtypes.

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

    // define a byte container based on std::vector
    using byte_container_with_subtype = nlohmann::byte_container_with_subtype<std::vector<std::uint8_t>>;

    using json = nlohmann::json;

    int main()
    {
        std::vector<std::uint8_t> bytes = {{0xca, 0xfe, 0xba, 0xbe}};

        // create container with subtype
        auto c1 = byte_container_with_subtype(bytes, 42);

        std::cout << "before calling clear_subtype(): " << json(c1) << '\n';

        c1.clear_subtype();

        std::cout << "after calling clear_subtype(): " << json(c1) << '\n';
    }

Output:

    before calling clear_subtype(): {"bytes":[202,254,186,190],"subtype":42}
    after calling clear_subtype(): {"bytes":[202,254,186,190],"subtype":null}

## Version history

Since version 3.8.0.

Last update: May 17, 2022
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