Playing around with Elixir macros

Macros.exs

defmodule My do
  defmacro if(condition, clauses) do
    
    do_clause = Keyword.get(clauses, :do, nil)
    else_clause = Keyword.get(clauses, :else, nil)
    
    quote do
      case unquote(condition) do
        _ in [false, nil] -> unquote(else_clause)
        _                 -> unquote(do_clause)
      end
    end  
  end

  defmacro unless(condition, clauses) do
    quote do
      if unquote(condition) do
        unquote(Keyword.get(clauses, :else, nil))
      else        
        unquote(Keyword.get(clauses, :do, nil))
      end

      unquote(Keyword.get(clauses, :finally, nil))

    end
  end

end

defmodule Test do
  require My

  My.if 1 == 2 do
    IO.puts "1 == 2"
  else
    IO.puts "1 != 2"
  end

  My.unless 1 == 1, 
    do: IO.puts("I shouldn't be run"), 
    else: IO.puts("I should be run"), 
    finally: IO.puts("Lastly, I should always be run!")

  My.unless 1 != 1, 
    do: IO.puts("Yes, me please"), 
    else: IO.puts("No, not me"), 
    finally: IO.puts("Thanks for the shoes")

end