/* What's up? This code illustrate capabilities of the library. There is operators, functions and overloaded functions of this library. This code is addition to topic: https://www.sololearn.com/Discuss/1240029/what-to-choose-tuple-or-struct Also more information of std::tuple could be found here: http://www.cplusplus.com/reference/tuple/ Whish you luck! */ #include // Class template std::tuple is a fixed-size collection // of heterogeneous values. #include // Function for wrapping given elements into tuple // and also printing them void print_pack(std::tuple pack) { std::cout<<'\n'<<' '<<' '<<' '<(pack)<<','<<' '; std::cout<(pack)<<'\n'; } // Main function starts here int main() { // Load data into tuple foo by naming type of every // element std::tuple foo (10,'x'); int myint; char mychar; // Unpack elements // basically release contain of foo into vars myint, mychar std::tie(myint, mychar) = foo; std::cout<<"\n1. print after simple std::tie(...) to variables: "; std::cout<<"\n\n myint="<(foo)<<' '; std::cout<(foo)<<'\n'; // Reload vars content: myint=11; mychar='r'; // Basically load contain of variables myint, // mychar into tuple foo std::get<0>(foo)=myint; std::get<1>(foo)=mychar; std::cout<<"\n2. Using std::get(x)=y:\n"; std::cout<<"\n variables containts: "; std::cout<<"myint="<(foo)<<' '; std::cout<(foo)<<'\n'; // Reload vars content: myint=23; mychar='v'; // Load data into tuples bar and pub without // naming type of every element auto bar = std::make_tuple("sense",65,72.6); auto pub = std::make_tuple(mychar,myint); std::cout<<"\n3. Using std::make_tuple(...):\n"; std::cout<<"\n bar contain: "; std::cout<(bar)<<' '; std::cout<(bar)<<' '; std::cout<(bar)<<'\n'; std::cout<<"\n pub contain: "; std::cout<(pub)<<' '; std::cout<(pub)<<'\n'; // std::tuple_size(...) get quatity // of elements in the tuple std::cout<<"\n4. Using std::tuple_size(...):\n"; std::cout<<"\n foo has "; std::cout<::value; std::cout<<" elements."<<'\n'; std::cout<<"\n bar has "; std::cout<::value; std::cout<<" elements."<<'\n'; std::cout<<"\n pub has "; std::cout<::value; std::cout<<" elements."<<'\n'; // Initialization of string someth, // it will be usefull next std::string someth = "any"; // Releasing contain of bar into vars mychar, myint // respectively, but string content of tuple bar // is ignored std::tie(std::ignore,mychar,myint) = bar; std::cout<<"\n5. print after std::tie(...) variables containts "; std::cout<<"\n by using std::ignore:\n\n"; std::cout<<' '<<' '<<' '<<"someth="<(bistro)<<' '; std::cout<(bistro)<<' '; std::cout<(bistro)<<' '; std::cout<(bistro)<<' '; std::cout<(bistro)<<' '; std::cout<(bistro)<<'\n'; std::string name ("Dmytro"); std::string surname1 ("Smith"); std::string surname2 ("Doe"); std::cout<<"\n8. print using std::forward_as_tuple: "<<'\n'; // Calling function print_pack(...) for printing names // with some numbers. print_pack(std::forward_as_tuple(name+' '+surname1,23)); print_pack(std::forward_as_tuple(name+' '+surname2,27)); // std::forward_as_tuple - is designed to forward arguments, // not to store its result in a named variable, since // the returned object may contain references // to temporary variables. // Tuple pack not accessible in the main function, // because it produce outside main function. // a.swap(b) is exchanges the content of the tuple object a // by the content of object b, which is another tuple // of the same type. // Priviously, was declared a tuples bar and caffe // and they are the same type. bar.swap(caffe); std::cout<<"\n9. Using a.swap(b):\n"; std::cout<<"\n bar contain: "; std::cout<(bar)<<' '; std::cout<(bar)<<' '; std::cout<(bar)<<'\n'; std::cout<<"\n caffe contain: "; std::cout<(caffe)<<' '; std::cout<(caffe)<<' '; std::cout<(caffe)<<'\n'; // template // class tuple_element< I, tuple >; // std::tuple_element is a class designed to access // the type of the Ith element in a tuple. // It is a simple class with a single member type, // tuple_element::type, defined as an alias of the // type of the Ith element in a tuple of type T. std::tuple_element<0,decltype(caffe)>::type caffe0 = std::get<0>(caffe); // it is basically the same that next: auto autocaffe0 = std::get<0>(caffe); std::cout<<"\n10. Using std::tuple_element::type :\n"; std::cout<<"\n caffe0 contain: "<(caffe),std::get<1>(caffe),23.4); std::cout<<"\n11. copycaffe contain: "; std::cout<(copycaffe)<<' '; std::cout<(copycaffe)<<' '; std::cout<(copycaffe)<<'\n'; std::cout<<"\n Caffe and copycaffe"; std::cout<<" are not equal - "; // std::boolalpha - is element from library // it help print exact word true or false std::cout<copycaffe)<<'.'<<'\n'; // And that's all folks return 0; }

tuple library capabilities