I’ve seen -> and <- used in Elixir books and articles, but I have not found a clear explanation to what they are called, and when they should be used. Generator Example: for n <- 1..4, do: n * n In an anonymous function, -> makes syntactical sense, but I don’t understand all of the use cases of <- …

Erlang And OTP in Action , p.42 2.3.4 Creating modules The arrow → is there to separate the function head (the name and arguments) from its body (what the function does). p.66 2.9.1 List comprehension notation You don’t have ∈ on your keyboard, so a left arrow ← is used to denote a generato…

Thank you. This makes sense now! :slight_smile:

-> is also used inside case and rescue clauses.

As @logicmason said above (a long time ago) the right arrow (aka stabby arrow) -> is also used for case and cond (more here in the guide ). You didn’t provide more details but I bet that in your case something0 is either a case or a cond. It might also be a rescue (and even more rarely maybe a recei…

Ill attach my question to this topic. I just refactored some code to use with and I wrote it with equal sign with {:ok, pid} = :file.open(@path, [:binary]), …

@dkuku It’s really easy to understand it. The best way is by practice, so let’s create an example code: defmodule Example do def sample(bool) do with true = bool do :ok else _ -> :error end end def sample2(bool) do with true <- bool do :ok else _ …

As always a good response, thanks.

Elixir Programming Language Forum

Syntax Question: -> and <-

Questions & Help Questions

silverdr March 23, 2020, 4:28pm 5

… and what does

something0
_ ->
  something1

mean?