Comparison typo in index_sequence_scan_impl::get

Dear Kokkos developers,

I believe I've found a mistake in the template specialization index_sequence_scan_impl<R, FirstVal> within include/experimental/__p0009_bits/extents.hpp.

In the get member function (lines 162 and 166), the current comparison logic seems wrong and inconsistent with the implementation on line 147.

• Current: Uses r < R or after the static_cast<int64_t> of each variable
• Expected: I believe the correct comparison should be R < r.

This can be check by

// currently: FirstVal = 8, the cummulative sum before element r = 2 (which is past FirstVal) should be 8
constexpr size_t r = 2;
static_assert((detail::index_sequence_scan_impl<0, 8>::get(r) == 8)); // Fails

Could you please take a look to see if this is indeed a bug or if I am misinterpreting the intended logic?

Best regards,

Elfego

Start in include/experimental/__p0009_bits/extents.hpp at the index_sequence_scan_impl<R, FirstVal>::get member function and compare the logic on lines 162 and 166 with line 147. Reproduce the provided constexpr static_assert, then verify the comparison behavior for the stated values. Done means the expected result is produced and regression coverage passes.