Simple intrusive linked list with no dependencies outside of the standard library. Requires C++17. Uses different implementation when being targeting the Itanium ABI.
pep::intrusive_list only lightly uses templates, the majority of the
implementation is in a base, non-templated class.
By default, it violates the standard by forward declaring
std::bidirectional_iterator_tag. This is to avoid including <iterator> which
chains multiple other headers(including ostream/istream, etc). If this is
undesired, define STUPIDLY_STD_COMPLIANT before including the header. I'm not
sure if all those headers being included is required by the standard(a brief
look didn't seem to require it), but libstdc++ does it.
pep::intrusive_node has an overhead of only 2 pointers. Nodes automatically
remove themselves from a list in their destructor.