How to bring the current context when a module is being executed into a module?

Questions / Help
1

I have this:

defmodule MyTest1 do
  def print_data do
    IO.puts("***this module: #{__MODULE__}")
  end
end

If I call it from within other module, it’ll still print the name of the original module --> Elixir.MyTest1.

How to change it such that it’ll print the name of a module it’s being called from? Without having to pass __MODULE__ to the function call.

2

One way would be to use a macro. But I think it’s generally recommended to only use macros if you really need them or if it really reduces boilerplate.

You can use __CALLER__ …

https://hexdocs.pm/elixir/Kernel.SpecialForms.html#CALLER/0

  defmacro print_data do
    quote do
      IO.puts("***this module: #{unquote(__CALLER__.module)}")
    end
  end

(edit: added __CALLER__ info)

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6

__MODULE__ is evaluated at compile time, that is why it will always show the module it is called in.

1 Like