Elixir：将多个变量传递给一个函数

Question

Elixir has the possibility to pipe input into a function, which makes code more readable very often.

For example something like this

sentence  |> String.split(@wordSplitter, trim: true)

which pipes the String sentence into the first argument of String.split .

Now consider I would also like to pipe the second argument into String.split . Is there a possibility to do that in Elixir? I mean something like this:

sentence, @wordSplitter |> String.split(trim: true)

Thanks!

Answer 1

As @Dogbert pointed out, this is impossible out of the box. The helper is pretty straightforward, though:

defmodule MultiApplier do
  def pipe(params, mod, fun, args \\ []) do
    apply(mod, fun, List.foldr(params, args, &List.insert_at(&2, 0, &1)))
  end
end

iex> ["a b c", " "]
...> |> MultiApplier.pipe(String, :split, [[trim: true]]) 
#⇒ ["a", "b", "c"]

iex> ["a b c", " ", [trim: true]]
...> |> MultiApplier.pipe(String, :split, [])             
#⇒ ["a", "b", "c"]

iex> ["a b c"]
...> |> MultiApplier.pipe(String, :split, [" ", [trim: true]])   
#⇒ ["a", "b", "c"]