Prevent Enum.map from converting to Keyword-List

Questions / Help
1

Enum.map converts results with 2-item-tuples where the first item is an atom to a keyword-list. This has it’s use cases, but when you want to keep the tuples, what is the idiomatic way to achieve this?

For example:
[1, 2, 3] |> Enum.map(& if &1 < 2, do: {:ok, "< 2"}, else: {:errror, "not < 2"})

returns

  ok: "< 2",
  errror: "not < 2",
  errror: "not < 2"
]

But I’d like to get this:

 {:ok, "< 2"},
 {:errror, "not < 2"},
 {:errror, "not < 2"}
]
2 Likes
2

They are the same thing!

https://hexdocs.pm/elixir/1.12/Keyword.html#module-examples

2 Likes
3

If you scroll a little bit up from the permalink shared by @lubien you will see the definition of a keyword list:

A keyword list is a list that consists exclusively of two-element tuples.

To hit it home: a keyword list is literally just a list like any other, the only thing “special” about is its very specific contents.

4

They are exactly the same, the former is just syntactic sugar.

Also you might want to correct “errror” (3 “r”-s) to “error” (2 “r”-s).

5

Oh yes, the docs are pretty clear at that.

Thnak you all for the quick repies!

1 Like