Best way to use derive with typedstruct module: .... do

[tcoopman]

This is what I want to write:

@derive Jason.Encoder
typedstruct module: Foo do
  field :bar, :string
end

> mix compile
warning: warning: module attribute @derive was set after defstruct, all @derive calls must come before defstruct

To fix it I have to use

require Protocol
Protocol.derive(Jason.Encoder, Foo)