Boost
C++ Libraries
...one of the most highly
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Alexandrescu, C++
Coding Standards
boost::container::allocator_arg_t
// In header: <boost/container/scoped_allocator_fwd.hpp> struct allocator_arg_t { };
The allocator_arg_t struct is an empty structure type used as a unique type to disambiguate constructor and function overloading. Specifically, several types have constructors with allocator_arg_t as the first argument, immediately followed by an argument of a type that satisfies the Allocator requirements