CODEWITHSUNDEEP
elixir
teddy tresor mabulay
teddy tresor mabulay

Reputation: 157

how to change a list from one format to another

I'm trying to change the format of a list using enum function.

The original list looks like this 

myInitialList = 
[
 {1,
   [
     ["A3", "Teddy"],
     ["B3", "[email protected]"],
     ["C3", "56123456"],
     ["D3", "spain"]
   ]},
  {2,
   [
     ["A4", "Katrin"],
     ["B4", "[email protected]"],
     ["C4", "85002145"],
     ["D4", "USA"]
   ]},
  {3,
   [
     ["A2", "name"],
     ["B2", "email"],
     ["C2", "phone"],
     ["D2", "country"]
   ]}
]

and I would like to filter the above list to have the below result

myFinalList = 
[
    %{
        name: "Teddy", 
        email: "[email protected]", 
        phone: "56123456", 
        country: "spain"
    }, 
    %{
        name: "Katrin", 
        email: "[email protected]", 
        phone: "85002145", 
        country: "USA"
    }
]

Does anyone have any idea how I can build the filter function?

This will allow me to easily insert the data in my database. I haven't really tried anything since I'm totally stuck from the beginning

in the code, it should look like 

myFinalList = myInitialList |> Enum.filter(.....)

Upvotes: 0

Views: 84

Answers (2)

Aleksei Matiushkin
Aleksei Matiushkin

Reputation: 121010

In the first place you need to split your input into names and actual values:

[names | items] = myInitialList |> Enum.reverse()

items here are in the reverse order, but it’s fine.

Now let’s define mapper:

mapper =
  fn {_, lists} -> Enum.map(lists, fn [_, e] -> e end) end

And, finally:

for values <- Enum.reverse(items),
  do: Enum.into(Enum.zip(mapper.(names), mapper.(values)), %{})

Upvotes: 0

jkmrto
jkmrto

Reputation: 104

You are looking for the Enum.map/2 function. Yo can get myFinalList with that format doing this:

myFinalList =
  Enum.map(myInitialList, fn
    {_index, [[_, name], [_, email], [_, phone], [_, country]]} ->
      %{
        name: name,
        email: email,
        phone: phone,
        country: country
      }
  end)

Upvotes: 1

Related Questions