end
  defp section_body(:code, binary) do
    vec(&code/1).(binary)

  defp code(binary) do
    {code_size, rest} = Atomic.u32(binary)
    {code, rest} = func(rest)
    {%{size: code_size, code: code}, rest}
  end
  defp func(binary) do
    {locals, rest} = vec(&locals/1).(binary)
    {e, rest} = expr(rest)
    {%{locals: locals, expr: e}, rest}
  end
  defp locals(:TODO) do
    :TODO
  end