Okay, now that Christmas and New Year is finally over and I’ve got pockets like a white eared elephant, I decided to have another blast at these tuple things because they were doing my head in.
All along I’ve been thinking that a class/struct would be much better. In most cases I would be right, but then I thought, “Hang on, this is C++. Let me check if I can return a tuple from a function.”
Hey, turns out I could.
#include <cstdlib>
#include <iostream>
#include <tuple>
using namespace std;
auto get_tuple(string name) {
return make_tuple(name, 1);
}
int main(int argc, char** argv) {
auto t3 = get_tuple("FOO");
auto t4 = get_tuple("BAR");
cout << get<0>(t3) << endl << get<0>(t4) << endl;
return 0;
}
And voila, just like that I can now return multiple values from a function.
The one thing you have to be careful of is the setup. A typo mistake or a type mistake can and will cost hours of debugging so be wary of things like this:
auto t1 = std::make_tuple("foo", 1, 2);
auto t2 = std::make_tuple("bar", 1.0, 2);
Now even if I added to the first tuple “foo”, 1f, 2, this would not match the second as the second tuple uses a double value. A pain for debugging.
Just the fact you can return multiple values of data without having to define a complete struct or class is actually quite a nice addition.
I have done some research into tuples now and found that these use cases are good, but for larger data, it is so much better even to still use a struct/class because with the above examples you still are having to use index values to access the data items. Where as a struct/class, the data items are named.
Although this however can be overcome by using enums, larger tuples are very likely better off being converted to a struct/class.
Even after 35+ years of programming I’m still learning.
Time to move onto something else… Bigger…
