My question is: how to best define functions so they compose nicely?

Here is the confusion. The following doesn’t work:

```
f(x) = x, x
g(a,b) = a+b
h = g∘f
h(1)
```

This produces a “MethodError: no method matching g(::Tuple{Int64,Int64})”

It works, however, if I add

```
g(xs) = g(xs...)
```

But I don’t really understand why. Much appreciated if someone can help me understand how to better define functions for composition.