CAIOHOBORGHI
Enum find by id?
How to find index of element inside enum by property?
I have this enum and I need to find the index of an item by its id(or another property).
[%{“code” => “ABEV3”, “comparison” => “>”, “field” => “close”, “id” => “4a9d96ce-e572-11eb-a557-0242ac170003”, “message” => “ABEV3 Close price is higher than 11.9!”, “value” => 11}]
How to do this?
Marked As Solved
Sebb
Sorry I most likely confused you with the hint that map-items are given as {k, v} to the function.
You have a list of maps, So you just do:
e = [%{foo: :bar, id: 1}, %{foo: :baz, id: 2}, %{foo: :foobar, id: 3}]
iex(3)> Enum.find_index(e, fn v -> v.id == 1 end)
0
So find_index goes through the list element by element, calls the function you provide and if this function return true, the index is returned.
Also Liked
Sebb
take a look at the great visual Elixir reference:
https://superruzafa.github.io/visual-elixir-reference/Enum/find_index/2/
hauleth
Pinning, so it will match the already bound value instead of rebinding. However in this case I think that it would be more readable to do:
Enum.find(list, fn elem -> elem.id == id end)
entone
you can also use pattern matching
Enum.find_index(list, fn %{id: ^id} -> true; _ -> false end)
you could also use filter to just remove the item
Enum.filter(list, fn %{id: ^id} -> false; _ -> true end)
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