I have a list of maps. For example, students = [%{ sid: 1, name: "Bob", score: 80}, %{ sid: 2, name: "Kelly", score: 60},.....] I have a function that accepts a single student map as a parameter, calculate_percentage(student) do something end I want to be able to pass each map in students list…

You did not specify what the calculate_percentage function should do and that is quite important. But if you want it to return a single value, you want to look at Enum.reduce. A reduce is one of the most fundamental operations in functional programming so it’s useful to learn it. With it, you can r…

I thought giving a simplified example would help. But the original list consists of a list of structs. And the I have written a function that accepts a single struct. a single struct looks like this %Post{ id : uuid, name: some name, feedbacks: [ %Comm…

No I don’t want the side effect. Is there a way to use Enum.each without getting :ok ? Enum.each works perfect for my requirement except for the fact that it returns :ok

I think you are confused about what is side-effect. A function converts inputs to outputs. If the function does only this and nothing else, it is called a pure function, or a function without side effect. A side effect is something you want to achieve in addition to the conversion: Writing databases…

If you don’t want the return values because you are in a function pipeline, you can use the new Kernel - tap/2 , introduced in Elixir 1.12

Thank you for explaining this. When I use Enum.each(posts, &IO.inspect/1), I get the following %Post{ id : uuid, name: some name, feedbacks: [ %Comment{ ........ }, %Comment{ …

[image] grangerelixx: I am not sure how to discard this :ok. Any thoughts on how we can discard :ok? Just don’t assign it to any variable? The REPL is a exploration vehicle; not your program. When you run your program for real you will have the full control of what to print and what not to p…

In elixir, everything is “discarded” except the last line of the function. For example: def my_func(param1, param2) do Database.query(param1) # returns list of users [%User{} ...] UserProfile.update!(param1, param2) # returns %UserProfile{} struct 1 + 1 end The only thing my_func is going t…

Elixir Programming Language Forum

Passing list values to a function

Questions & Help Questions

derek-zhou June 9, 2021, 7:20pm 3

If you want side effect only, then use Enum.each/2