How do I transform a large, often-used C++ macro with trivial per-use changes into a C++ template or similar? -

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i'm working on container, has code similar following pseudocode:

#define large_insert_macro (assignment_object) \ if (some_stuff) \ { \     ... more stuff ... \     allocator.construct(place_to_insert_to, assignment_object); \     ... etc ... \ } \ else if (other_stuff) \ { \     ... different stuff ...  \     allocator.construct(place_to_insert_to, assignment_object); \     ... etc ... \ } \ else \ { \     ... other different stuff ... \     allocator.construct(place_to_insert_to, assignment_object); \     ... etc ... \ } \ ... more stuff again... \   iterator insert(the_type &object) {     large_insert_macro(object) }   iterator insert(the_type &&object) {     large_insert_macro(std::move(object)) }   template<typename... arguments> iterator emplace(arguments... parameters) {     large_insert_macro(parameters...) }

given fact code before , after each insertion type both necessary insertion, not change between insertion types , cannot factored away 2 separate 'before , after' functions, how can piece of (pseudo)code changed no longer uses macros?

as always, stay on topic of changing macros other code forms - please.

the answer dump large insert macro altogether , allow wonder of universal reference deduction work you:

template<class thetype> iterator insert(thetype&& object)  // object deduced either r-value                                // or l-value reference required context {     if(some_stuff) {         ...         return allocator.construct(place_to_insert_to, std::forward<thetype>(object));     } else {         ... , on     } }

emplace without template argument @ call site possible when it's member function of container knows type contains. otherwise have specify it. again, note use of universal reference deduction perfect forwarding of arguments.

template<class thetype, typename... arguments>  iterator emplace(arguments&&... parameters) {     return insert(thetype(std::forward<arguments>(parameters)...)); }

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