owaisqayum
How can we create a nested keyword list
How can we create a nested keyword list from the following list. The list length can change with time.
list
[:a, :b, :c, :d, :e, :f]
how can we convert it to
[a: [b: [c: [d: [e: [f: [ true ] ]]]]]]
Is it possible with elixir as I tried to use recursion but it’s not working as expected.
Thanks
Marked As Solved
kokolegorille
iex> l |> Enum.reverse() |> Enum.reduce([true], fn x, acc -> Keyword.new([{x, acc}]) end)
[a: [b: [c: [d: [e: [f: [true]]]]]]]
# or the short version...
iex> l |> Enum.reverse() |> Enum.reduce([true], &Keyword.new([{&1, &2}]))
Also Liked
gregvaughn
Perhaps a bit 
ish, but I’ve never actually used foldr before, so I put this together 
iex(40)> :lists.foldr(&[{&1, &2}], [true], [:a, :b, :c, :d, :e, :f])
[a: [b: [c: [d: [e: [f: [true]]]]]]]
eksperimental
You have List.foldr/3 if you want to make it more Elixirish.
kokolegorille
When You have an Enumerable, and want to get one value… the usual suspect is Enum.reduce.
iex> l = [:a, :b, :c, :d, :e, :f]
iex> Enum.reduce l, [], fn x, acc -> Keyword.put([], x, acc) end
# or
iex> Enum.reduce l, [], fn x, acc -> Keyword.new([{x, acc}]) end
[f: [e: [d: [c: [b: [a: []]]]]]]
This code does not solve your problem, but shows how to nest… I would reverse the list first, and add the final true to get it work.
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