I have different structs returned from database and i want to replace the value Ecto.Assoication.Notloaded with some custom value like not loaded in all of them. This is one record unit = %{ __meta__: #Ecto.Schema.Metadata<:loaded, "units">, cdc_location_class_id: nil, description: "", …

You can use Enum.map or :maps.map for it. unit |> Enum.map(fn {k, %Ecto.Association.NotLoaded{}} -> {k, "not loaded"} other -> other end) |> Enum.into(%{}) or :maps.map(fn _k, %Ecto.Association.NotLoaded{} -> "not loaded" _k, v -> v end, unit)

Try something like: defp replace_not_loaded_value({k, %Ecto.Association.NotLoaded{}}) do {k, "not loaded"} end defp replace_not_loaded_value({k, v}), do: {k, v} unit |> Map.to_list() |> Enum.map(&replace_not_loaded_value/1) |> Enum.into(%{})

You can try this too… unit |> Enum.reduce(%{}, fn {k, %Ecto.Association.NotLoaded{}}, acc -> Map.put(acc, k, "not loaded") {k, v}, acc -> Map.put(acc, k, v) end) Each time I see a map … into, I feel reduce might do the same in one iteration. I did not benchmark, but this really is only one …

[image] kokolegorille: Each time I see a map … into, I feel reduce might do the same in one iteration Each time I see a map … into with a Map argument, I reach for Map.new