I decided to implement a new class based on std::variant. I call it "rpnx::derivator", but it's basically "allocating_variant". I tried to make it as similar to std::variant as possible. When looking at this, I noticed something weird about std::variant. There is no "zero overhead" way to get the element contained by the variant, as std::get<I> checks for invalid access and throws an exception if invalid. To solve this issue, I would like to propose std::as, which works the same as std::get, but accessing the wrong type is undefined behavior instead of throwing an exception.

--
Ryan P. Nicholl
Tel: (678)-358-7765
Personal Email: rnicholl_at_[hidden]
Work Email: ryan.nicholl_at_[hidden]
Tox: 52B3A61CDAF88BCC854F568933F071E3530600CDBA3D5354AADC9AD179575D68021AE959719D