What is the lifetime or scope of module attributes if declared before function definitions?

Questions / Help
1

Should module attributes reset after every function definition or does ExUnit reset @tag with macros?

Would I need @doc false for second/0 if I had a @doc for first/0 and third/0?

defmodule MyApp do

  @tag 0

  @tag 1
  def first() do
    @tag |> IO.inspect() # prints 1
  end

  def second() do
    @tag |> IO.inspect() # prints 1
  end

  @tag 3
  def third() do
    @tag |> IO.inspect() # prints 3
  end

end
2

Excellent question. Module attributes are not reset by default.

However, if def or test “use” an attribute, then they also reset it. So def will use and reset any @doc. test will use and reset any @tag. Etc. In ExUnit, if you want to set a tag for everything, then you have @moduletag and @describetag.

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