With the following code:

```
def index
  @q = ""
  @q = params[:search][:q] if params[:search]
  q = @q
  @search = Sunspot.search(User) do
    keywords q
  end
  @users = @search.results
end

```

If @q is used instead of q, the search always returns results for an empty query (""). Why is this?
Is the @q variable unavailable to the do...end block?