iex_helper.ex

iex>h Enum.map

                            def map(enumerable, fun)

    @spec map(t(), (element() -> any())) :: list()

Returns a list where each item is the result of invoking fun on each
corresponding item of enumerable.

For maps, the function expects a key-value tuple.

## Examples

    iex> Enum.map([1, 2, 3], fn(x) -> x * 2 end)
    [2, 4, 6]

    iex> Enum.map([a: 1, b: 2], fn({k, v}) -> {k, -v} end)
    [a: -1, b: -2]