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kotlinlang

Using `ListK.applicative()` and `tupled(listA.k(), listB.k()`, I can generate all `Tuple2`'s with the elements in both lists. If I give more arguments to `tupled`, then I get a `Tuple3`, etc. Is there a way to give more arguments to a method like `tupled` but still only get a `Tuple2` out? I want to get all the pairs of elements between n lists.

The issue here is that you want to obtain a Tuple2&lt;A, B&gt; from the result of parameterizing over n lists like List&lt;A&gt;, List&lt;B&gt;, List&lt;C&gt;,…

so once you have C? how do you represent the fact that Tuple2 is parametric to two type argument whereas ListN  can have arbitrary arity and therefore produce more than than A and B

What would be the function signature regardless of implementation that you expect?

Based on your comment I´m reading…
```
fun &lt;A, B, C&gt; unknown(la: List&lt;A&gt;, lb: List&lt;B&gt;, lc: List&lt;C&gt;): List&lt;Tuple2&lt;?, ?&gt; = TODO()
```

I agree that general case isn't reasonable, but I was thinking:
```
fun &lt;A&gt; tupled(a: List&lt;A&gt;, b: List&lt;A&gt;, c: List&lt;A&gt;): List&lt;Tuple2&lt;A, A&gt;&gt; = TODO()
```

All the pairs of `a` and `b`, all the pairs of `b` and `c`, and all the pairs of `a` and `c`.