elixir - Inconsistent Functions behavior

Question

I'm trying out a square and a cube function. Why does square work while cube blows up?

square = &1 * &1
square.(5)

Works fine while

cube = &1 * &1 * &1
cube.(5)

Throws

** (ArithmeticError) bad argument in arithmetic expression
    :erlang.*(#Function<erl_eval.6.82930912>, 5)
    erl_eval.erl:572: :erl_eval.do_apply/6
    src/elixir.erl:133: :elixir.eval_forms/3
    /private/tmp/elixir-OVih/elixir-0.8.2/lib/iex/lib/iex/server.ex:19: IEx.Server.do_loop/1

question from:https://stackoverflow.com/questions/16997059/inconsistent-functions-behavior

Answer 1

Since 0.10.3 you need to put the partial application between parentheses preceded by the & operator.

You won't have any trouble with this version:

iex> square = &(&1 * &1)
iex> square.(5)
25
iex> cube = &(&1 * &1 * &1)
iex> cube.(5)
125