<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/60995>60995</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            `<format>`: The definition of `__fmt_pair_like` is wrong
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          hewillk
      </td>
    </tr>
</table>

<pre>
    https://github.com/llvm/llvm-project/blob/9d53c8684fe2a8b14505593d7e470dac1f68dbd7/libcxx/include/__format/concepts.h#L67-L70

`requires { tuple_size_v<_Tp> == 2; }` should only require the expression to be valid and not actually evaluate it, right?

https://godbolt.org/z/c6aMq4xzd
```cpp
#include <iostream>
#include <vector>
#include <format>

int main() {
 std::vector<std::tuple<>> v(3);
  std::cout << std::format("{:nm}", v); // (), (), ()
}
```
</pre>
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