How to update or remove a struct from array?

Questions / Help
,
1

Hi. new to elixir. I need to remove a struct or update it from given array of structs

array = [%{id: "1", img: "2", tokens: "3"}, %{id: "2", img: "2", tokens: "3"},
 %{id: "3", img: "2", tokens: "3"}]

Thanks in advance

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2

Hey @newbie1 welcome!

Can you sketch what kind of change you need to make, and how you’re going to identify each struct? Do you need to update a specific one by ID?

Also as a minor note you can format the code by doing ``` before and after the text. I’ve edited your post by way of example.

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@benwilson512 what i want is remove %{id: “1”, img: “2”, tokens: “3”} from array so it would look like

array = [%{id: "2", img: "2", tokens: "3"}, %{id: "3", img: "2", tokens: "3"}]

or update it like %{id: “1”, img: “4”, tokens: “4”} so my array would look like

 %{id: "3", img: "2", tokens: "3"}]```
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4

Sure! In your case you’ve got a couple options. It’s the first item in the list so one option is to just take the tail of the list:

list = tl(list)

If you want to remove any maps with id: 1 regardless of where they are in the list you can just filter them out:

list = Enum.reject(list, fn item -> item.id == "1" end)

If you talk a bit about what you’re using this list for we can also recommend some other data structures that may be more relevant. For example if you’re mostly focused on just having a set of structs and referring to them by ID a map may be more useful:

map = %{
  "2" => %{id: "2", img: "2", tokens: "3"},
  "3" => %{id: "3", img: "2", tokens: "3"},
}

This would let you do Map.delete(map, "2")

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@benwilson512 second option did the trick. Thank you

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To add to @benwilson512’s answer: There are a couple of libraries that abstract the map syntax away from you, like the arrays package I maintain. :angel:

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