* and_condition_impl::combine_equal - Remove UB container modification.

The container is modified while iterating it.
Switched to indexed based iteration to avoid UB.

* Update condition.cpp

Sorry missed this line.

* Proposed fix for comparing floating points (needed on macOS)

* Work around weird behaviour in testing floats using catch2

* Better from_chars implementation

fix ordering atoms

example should work when there is no components.cif file yet

replace size_t with std::size_t to silence warnings