@brief returns a reference to the output stream

The ios standard format doesn't use char separators

The following 3 should only be used after fill has been called

Specifies an implicit value, which will be used if the option is given, but without an adjacent value. Using this implies that

member functions index(), value() (non-const and const)

@copydoc ::boost::intrusive::bstree_algorithms::is_header

std::lexicographical_compare would infinately recurse because path iterators yield paths, so provide a path aware version

Function pointers