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Regarding your point about cleaning up other people's macros.

In Elixir macros are imported into local scope only when the user explicitly asks for it. Most libraries provide a `__using___` macro that can modify current scope.

For instance, `use ExUnit.Case` allows you to write tests like this

    test "my test case" do
      assert funcall() == "value"
    end
instead of this

    require ExUnit.Case
    ExUnit.Case.test "my test case" do
      ExUnit.Assertions.assert funcall() == "value"
    end
So it basically imports a bunch of stuff for you, but only when you call `use ExUnit.Case`.

The consensus in the community right now is to not get carried away with macros and DSLs. Even if your library provides a DSL, it should be based on a functional API that is mostly usable without macros.

And lastly, remember that `use`, `require`, and `import` modify only the current lexical scope. I wrote this macro[1] that replaces the built-in `|>` operator with a version that prints its output to the console. You can `use PipeInspect` inside one function and only that function's body will get the overriden implementation of `|>`.

Cheers.

[1]: https://gist.github.com/alco/9956215



> The consensus in the community right now is to not get carried away with macros and DSLs. Even if your library provides a DSL, it should be based on a functional API that is mostly usable without macros.

Yup. But what people say and what people do is often not the same thing :).


Sure. I just wanted to stress the point that macros are local in their scope. It's nothing like monkey-patching in Ruby where importing a module can change all divisions from floats to rational numbers.




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