...one of the most highly
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— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::intrusive::pointer_plus_bits
// In header: <boost/intrusive/pointer_plus_bits.hpp> template<typename Pointer, std::size_t NumBits> struct pointer_plus_bits { };
This is class that is supposed to have static methods to embed extra bits of information in a pointer. This is a declaration and there is no default implementation, because operations to embed the bits change with every pointer type.
An implementation that detects that a pointer type whose has_pointer_plus_bits<>::value is non-zero can make use of these operations to embed the bits in the pointer.