I have two tuples like this

```
std::tuple<std::vector<int>, std::vector<int>> t1; 
std::tuple<std::vector<int>, std::vector<int>> t2; 

```

I now want to concat the entries of the tuples (so that I have one tuple containing two vectors with the entries of the the first/second vectors of the tuples). It is fine if the tuple is mutated.

I can do this like this:

```
std::get<0>(t1).insert(std::get<0>(t1).end(), std::get<0>(t2).begin(), std::get<0>(t2).end());

```

for each entry, but if i have a lot if entries in the tuple, it becomes very ugly.

Iterating the tuple with a normal for loop does not work since `std::get` requires a constant. I did not get it to work with `std::apply` because only one argument can be passed.