Possible mistake in the Getting Started example for "Enumerables & Streams/Eager vs Lazy"

[akitaonrails]

I was trying this example from this section in the Getting Started guide:

1..100_000 |> Stream.map(&(&1 * 3)) |> Stream.filter(odd?)

It blows the following error:

** (CompileError) iex:18: undefined function odd?/0
    (elixir) expanding macro: Kernel.|>/2
             iex:18: (file)

I think the correct example would be using the Integer.is_odd macro, wouldn't it?

require Integer
1..100_000
  |> Stream.map(&(&1 * 3))
  |> Stream.filter(&(Integer.is_odd(&1)))
  |> Enum.sum

[josevalim]

Hi @akitaonrails! :D We did define the odd? function in the previous section: http://elixir-lang.org/getting-started/enumerables-and-streams.html#eager-vs-lazy

Maybe we should make it clearer?

[josevalim]

@akitaonrails I am closing this but please let me know if you think we can make it clearer. Thank you! :D

[akitaonrails]

Ah, sorry, you're right :-) I was copying this snippet to use in a presentation (I say it's from the getting started in the site), so without context it fails, but following step by step it does work. Not a bug, just out of context from my part indeed.