It Intersect

seq1 := func(yield func(int) bool) {
    _ = yield(1)
    _ = yield(2)
    _ = yield(3)
    _ = yield(4)
}
seq2 := func(yield func(int) bool) {
    _ = yield(2)
    _ = yield(3)
    _ = yield(5)
}
seq3 := func(yield func(int) bool) {
    _ = yield(3)
    _ = yield(2)
    _ = yield(6)
}
intersection := it.Intersect(seq1, seq2, seq3)
var result []int
for v := range intersection {
    result = append(result, v)
}
// result contains 2, 3 (elements present in all sequences)