defmodule Infix do
  defmacro __using__(opts \\ []) do
    arithmetic = Keyword.get(opts, :arithmetic, [
      {:+, 2},
      {:-, 2},
      {:*, 2},
      {:/, 2},
    ])

    comparison = Keyword.get(opts, :comparison, [
      {:>, 2},
      {:>=, 2},
      {:<=, 2},
      {:==, 2},
      {:===, 2},
      {:!=, 2},
      {:!==, 2}
    ])

    overrides = arithmetic ++ comparison

    quote do
      import Kernel, except: unquote(overrides)
      import Infix.Comparison, only: unquote(comparison)
      import Infix.Arithmetic, only: unquote(arithmetic)
    end
  end
end