CBP is made up of personnel who were formerly with the U.S customs, U.S Immigration, Animal and Plant Health Inspection Service and the entire U.S Border Patrol. The Department of Homeland Security was established on March 1, 2003, including the creation of U.S. Customs and Border Protection (CBP).
function templates are special functions that can operate with generic types this allows us to create a function template whose functionality can be adapted to more than one type or class without repeating the entire code for each type in c++ this can be achieved using template parameters a template parameter is a special kind of parameter that can be used to pass a type as argument just like regular function parameters can be used to pass values to a function template parameters allow to pass also types to a function
(since C++11). Class template std::function is a general-purpose polymorphic function wrapper. Instances of std::function can store, copy, and invoke any Callable target -- functions, lambda expressions, bind expressions, or other function objects, as well as pointers to member functions and pointers to data members. The stored callable object is called the target of std::function. If a std::function contains no target, it is called empty. Invoking the target of an empty std::function results in std::bad_function_call exception being thrown. std::function satisfies the requirements of CopyConstructible and CopyAssignable.