pipeline.ex

defmodule Pipeline do
  defmacro __using__(_) do
    quote do
      import Kernel, except: [~>>: 2]
      import Pipeline
    end
  end

  defmacro lhs ~>> rhs do
    quote do
      case unquote(lhs) do
        {:ok, value} -> value |> unquote(rhs)
        other -> other
      end
    end
  end
end

Why have you imported kernal and excepted ~>>. Is that just good form in case ~>> arrives in kernal in the future

Yeah. It isn't really necessary, though.

https://github.com/CrowdHailer/OK

Though a bit more work is needed to make it work with named function properly