Generating combinations using next_permutation

[someone]

I was told that it was possible to generate combinations of a set of elements using next_permutation. Does somebody know anything about that?

[jsmith]

Combinations and permutations are two different things. With next_permutation it is possible to
generate permutations, not combinations.

[someone]

I know what's the difference between them. But I was told it was possible to generate combinations with next_permutation, too! And I wonder how...

[jsmith]

There isn't a way that I can think of that doesn't require a lot of extra code.