I have a function that takes in any number of vectors, not necessarily of equal length:

```
function exfnc(x::Vector{Float64}...)
sizes = length.(x)
## compute some function over all combinations (x1[i], x2[j], ..., xn[k])?
end
```

Say there are `n`

such vectors and I have some function that takes in this `n`

-vector. I want to compute this function over all possible combinations of the elements between each vector. For example, if I only had to consider three arguments, I could write something like:

```
function exfnc(x₁, x₂, x₃)
for k in eachindex(x₃)
for j in eachindex(x₂)
for i in eachindex(x₁)
val = f(x₁[i], x₂[j], x₃[k]) # some function f
# do something with val...
end
end
end
end
```

Is there a way to form this type of loop for the `Varargs`

case?