Flatter.ex

defmodule Flattery do
  def run({a, b}, acc)
      when is_map(b) == false,
      do: Map.merge(acc, %{a => b})

  def run({_a, b}, acc)
      when is_map(b),
      do: go(b, acc)

  def run({a, b}, acc),
    do: Map.merge(acc, %{a => b})

  def go(enum, acc \\ %{})

  def go(enum, acc) do
    Enum.reduce(enum, acc, &run/2)
  end
end

Sometimes we forget things. Is there an existing function on Map or Enum to flatten a map with many nested maps.

#> Flattery.go(%{foo: %{bar: 1, baz: %{bingo: 2, basic: %{zed: 3}}}})
#> %{bar: 1, bingo: 2, zed: 3}