[Bug c++/100157] Support `__type_pack_element` like Clang

[pdimov at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100157

Peter Dimov <pdimov at gmail dot com> changed:

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                 CC|                            |pdimov at gmail dot com

--- Comment #11 from Peter Dimov <pdimov at gmail dot com> ---
Just import mp11 wholesale and use mp_at_c and mp_find :-)