Hey there :waving_hand: I have the 2 following structs. defmodule Variation do @enforce_keys [:id, :attributes] defstruct [:id, :description, :attributes, :slots, :block] end defmodule VariationGroup do @enforce_keys [:id, :variations] defstruct [:id, :description, :variations] end I wou…

Another options: def test(%module{}) when module in [Variation, VariationGroup], do: ... def test(term) when is_struct(term, Variation) or is_struct(term, VariationGroup), do: ...

Just treat them as maps: def my_func(%{id: id, attributes: attributes}) do # work end And if you need to access the underlying module: def my_func(%{id: id, attributes: attributes} = entity) do entity.__struct__ end

I will actually use both of your solutions. Guard + map attribute pattern matching Thanks!

Don’t you still have to know which one you have when you work with them?

I have a general purpose loop that doesn’t need to know which one is which. Then I also have specific functions that precisely pattern match against either %Variation{} or %VariationGroup{}

I just realized that what I’m looking after is polymorphism for structs. But I don’t think this is available in Elixir. Is it?

But what if I also want an implementation that apply on both structs?

If you want to share the implementation of a function from a protocol, you can move it to a different module and delegate there from all separate protocol implementations. Or you can create a separate protocol for the shared parts and pass a list of struct modules (or primitive types if applicable) …

Elixir Programming Language Forum

Struct pattern matching

Questions & Help Questions

michallepicki July 30, 2022, 9:20am 8

You can define a Protocol and have separate implementation for each struct