Fix Reflection found bug

[schaumb]

Hi!
Thanks for the library.
I made a fix for the boost pfr member name reflection. Can you apply it to this repository?
non-internal linkage

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I would be pleased if you could mention anywhere that this reflection method was found by me here.

[stephenberry]

Awesome! I will look into this and be sure to credit you. Thanks for sharing!

[stephenberry]

@schaumb, this does not appear to work with Clang 15.

[schaumb]

It's working.
https://godbolt.org/z/W9j866Ejv

On clang, you need to wrap member pointer to a class because it's not C++ compliant

[stephenberry]

@schaumb Neat, thanks for the compiler explorer link! But, I fail to see how your changes offer any improvement if I need an extern template wrapper? It isn't eliminated my need for an extern template. What would I be gaining?

[schaumb]

Currently, you cannot reflect on aggregate types with internal linkages, like function locale classes, unnamed classes, or classes inside the unnamed namespace. My fix enables these classes to reflect.