Parallelized collection processing w/ sub-process supervision

process.ex

alias Task.Supervisor

{:ok, supervisor} = Supervisor.start_link

double = fn(n) -> n*2 end

[1, 2, 3]
|> Enum.map(&Supervisor.async(supervisor, fn -> double.(&1) end))
|> Enum.map(&Task.await/1)
#=> [2, 4, 6]

[1, 2, "ruhroh"]
|> Enum.map(&Supervisor.async(supervisor, fn -> double.(&1) end))
|> Enum.map(&Task.await/1)
# 10:56:29.550 [error] GenServer #PID<0.63.0> terminating
# Last message: {:EXIT, #PID<0.58.0>, {:badarith, [{:erlang, :*, ["ruhroh", 2], []}, {Task.Supervised, :do_apply, 2, [file: 'lib/task/supervised.ex', line: 74]}, {Task.Supervised, :reply, 3, [file: 'lib/task/supervised.ex', line: 50]}, {:proc_lib, :init_p_do_apply, 3, [file: 'proc_lib.erl', line: 237]}]}}

Follow up Elixir homework to https://github.com/elixir-lang/ex_doc/pull/227/files.

Thanks to @peregrine for the nudge