Learning resources about dialyzer?

[kokolegorille]

@BartOtten

   case arg do
     1 -> :ok
     _other -> :error
 end

In case You want to catch something like this, You could do

   case arg do
     1 -> do_ok()
     _other -> do_error()
 end

and give spec to the do_ok, do_error functions, as mentionned in this previous post

Type and spec - Dialyzer not detecting error

Hello everyone, I have been reading this book [Functional Programming] Domain Modeling Made Functional (Pragprog) (F#) and liked it a lot. I am trying to mimic conditional type from F# to Elixir with the use of spec, type and dyalixir defmodule Ddd.OrderTaking do @type result :: :ok | :error @spec create_unit_quantity(integer) :: result def create_unit_quantity(qty) when is_integer(qty) do cond do qty < 0 -> :error qty > 1_000 -> :error true -> :ok end end end If …