<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/148179>148179</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            P2781R9: `std::constant_wrapper`
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            libc++,
            c++26,
            wg21 paper
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          frederick-vs-ja
      </td>
    </tr>
</table>

<pre>
    **Link:** https://wg21.link/P2781R9

Feature-test macro
```c++
#define __cpp_lib_constant_wrapper 202506L // freestanding, also in <type_traits>
```
</pre>
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