c++ - Can a range-based for loop take a type argument? -

from can tell, range-based loops can take c-style array, object of type has member functions begin() , end() defined, or object of type type free functions begin(type) , end(type) can found adl.

is there way make loop take type argument, code compiles?

class staticvec{ //shortened implementation     static myiterator begin();     static myiterator end(); };  void foo() {     for(auto elem : staticvec){        dosomething(elem);     } } 

i omit necessity of writing staticvec::values() in loop.

as general solution can define

template< class type > struct static_collection {};  template< class type > auto begin( static_collection<type> const& )     -> decltype( type::begin() ) { return type::begin(); }   template< class type > auto end( static_collection<type> const& )     -> decltype( type::end() ) { return type::end(); } 

and can write e.g.

auto main() -> int {     for( auto elem : static_collection<static_vec>() )     {         std::cout << elem << ' ';     }     std::cout << '\n'; } 

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addendum:
in practical cases suffice create instance of class holding static begin , end member functions, shown in jarod42’s , matt mcnabb’s answers (the former posted when posted above), e.g.

for( auto const& elem : staticvec() ) {     // ... } 

if instance creation can have undesirable side effects, or perhaps after future maintainance work, use general solution.

otherwise, if instance creation free, i’d go that.