   ## Example
 
       # In ~/.iex.exs
-      import_if_available Ecto.Query
+      import_if_available(Ecto.Query)
 
   """
   defmacro import_if_available(quoted_module, opts \\ []) do

  expanded:

      # This raises a File.Error if ~/.iex.exs doesn't exist.
      if ("~/.iex.exs" |> Path.expand |> File.exists?) do
        import_file "~/.iex.exs"
      end

  This macro addresses this issue by checking if the file exists or not

      value = 13

      # in the shell
      iex(1)> import_file("~/file.exs")
      13
      iex(2)> value
      13
