This code produces what I want, which is a TypedArray containing [12, 34, 56]:

function * f() {
  for (c of [12, 34, 56]) {
    yield c;
  }
};
t = new Uint8Array(f());

I expected this to do the same thing, but it just creates an empty array:

t2 = new Uint8Array(function *() {
  for (c of [12, 34, 56]) {
    yield c;
  }
})

What am I doing wrong?