alco

bin = "HELLO"

spawn(fn ->
  raise ArgumentError, message: "Unsupported or invalid status #{bin}"
end)

alco

iex(1)> bin = "HELLO"
"HELLO"
iex(2)> raise ArgumentError, message: 'Unsupported or invalid status #{bin}'
** (ArgumentError) Unsupported or invalid status HELLO

alco

iex(1)> raise 'foo'
** (ArgumentError) argument error
     :erlang.apply('foo', :exception, [[]])

alco

λ iex -S mix
iex(1)> Dbg.trace(self(), :call)
{:ok, [{:matched, :nonode@nohost, 1}]}
iex(2)> Dbg.call(Mix.Task, :stack)
{:ok, [{:matched, :nonode@nohost, 20}, {:saved, 1}]}
iex(3)> args = []
[]
iex(4)>         Mix.Task.run("run", ["test/fixtures/help_cmd.exs"|args])
:noop
iex(5)> 

alco

iex(1)> OptionParser.parse(["--hello", "world"]) 
{[hello: "world"], [], []}

iex(2)> OptionParser.parse(["--hello", "world"], switches: [hello: [:string]])
{[hello: "world"], [], []}

iex(3)> OptionParser.parse(["--hello", "world"], switches: [hello: [:string, :optional]])
{[hello: nil], ["world"], []}

iex(4)> OptionParser.parse(["--hello=world"], switches: [hello: [:string, :optional]])   

alco

λ iex my.ex 
Erlang/OTP 17 [erts-6.0] [source] [64-bit] [smp:8:8] [async-threads:10] [hipe] [kernel-poll:false] [dtrace]

Interactive Elixir (0.13.3-dev) - press Ctrl+C to exit (type h() ENTER for help)
iex(1)> use My
nil
iex(2)> 3&&4
81.0

alco

defmodule Beamie.Store.RiakHTTP do
  def put(bucket, key, value) do
    IO.puts "storing value #{inspect value} with key #{key} in bucket '#{bucket}'"
    put_req(bucket, key, value)
  end

  def get(bucket, key) do
    IO.puts "retrieving value for key #{key} from bucket '#{bucket}'"
    get_req(bucket, key)
  end

alco

# attr.exs

# using module attributes as compile-time constants
defmodule M do
  @constant 13

  def a, do: @constant

  @constant 44

alco

iex(3)> """abc
...(3)> bcd"""
...(3)> """
...(3)> """
...(3)> """
...(3)>

alco

defmodule Bag do
  defstruct store: %{}

  def new do
    %Bag{}
  end

  def put(%Bag{store: store}, thing) do
    %Bag{store: Map.update(store, thing, 1, &( &1 + 1))}
  end