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<td class="t-dcl-nopad"> </td> <td > (since C++11) </td> </tr> Template:ddcl list end
std::allocator_arg is a constant of type std::allocator_arg_t used to disambiguate, at call site, the overloads of the constructors and member functions of allocator-aware objects, such as std::tuple, std::function, std::promise, and std::packaged_task.