Hi,
I have a recuring pattern that I feel could be done better. There's a list
of 2-tuples where the tuples are {key, value} pairs. The same key can be
there more than once in the list. I want to transform it into a map where
the keys are the keys from the tuples and the values become lists of all
the values coming from the tuples with the same key. (The order in the
list doesn't matter.)
For examle:
list_of_tuples = [{1, 2}, {1, 3}, {1, 4}, {2, 3}, {2, 4}, {3, 4}, {5,
6}]
--> %{1 => [2, 3, 4], 2 => [3, 4], 3 => [4], 5 => [6]}
I used to do this with the following transformation:
list_of_tuples
|> Enum.group_by(&(elem(&1,0)))
|> Enum.map(fn {k, v} -> {k, Enum.map(v, &(elem(&1, 1)))} end)
|> Enum.into(%{})
Is there any better or more elegant way?
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