defmodule TestMacro do
  defmacro test_macro do
    quote do
      IO.inspect(var!(name))
    end
  end
end

defmodule Gen do
  defmacro __using__(_args) do
    quote do
      @before_compile unquote(__MODULE__)
    end
  end

  defmacro __before_compile__(_env) do
    quote do
      def test do
        name = "test"
        test_macro
      end
    end
  end
end

defmodule User do
  import TestMacro
  use Gen
end


# ** (CompileError) iex:6: expected var "name" to expand to an existing variable or be part of a match
#     (elixir) expanding macro: Kernel.var!/1
#              iex:6: User.test/0
#              expanding macro: TestMacro.test_macro/0
#              iex:6: User.test/0
#              iex:6: Gen.__before_compile__/1