In “Elixir in Action”, there is an example about using pattern matching with the “with” special form: with {:ok, login} <- extract_login(user), {:ok, email} <- extract_mail(user), {:ok, pw} <- extract_pw(user) do {:ok, %{login: login, email: email, pw: pw}} end If eac…

One way how to do it: 7) ElixirConf US 2018 – Architecting Flow in Elixir - From Leveraging Pipes to Designing Token APIs – René Föhring

You could reduce each function call… then check if Enum.all?, Enum.any?, whatever tests You may want to run on the list. # NOT TESTED! result = ~w(extract_login extract_mail extract_pw)a |> Enum.reduce(&apply(__MODULE__, &1, [user])) But your code looks like a user validation, and usually this ca…

Something like this, (I haven’t run the code though) validations = [ login: &extract_login/1, mail: &extract_mail/1, pw: &extract_pw/1 ] Enum.reduce(validatations, [], fn {key, validate_fun}, acc -> case validate_fun.(user) do {:ok, value} -> [{:ok, key, value} | acc] :error…

This looks like what I was doing in Java, where functional programming idioms are at last available. I was hoping there were a macro or special form like with that might accomplish what that reduce is doing there. I’m still learning the bare basics. Thank you!

Whoa your sigil just blew my mind. I didn’t know that was a thing yet. Thank you. I’ll need to read about changesets.

I just started with Elixir - this is way over my head. I’ll revisit in a few months. Thanks

How would you accumulate errors?

Questions & Help Questions

eksperimental June 6, 2022, 1:21am 7

you can use

for {key, validate_fun} <- validation, reduce: [] do
  acc ->
   ....
end