Enum.map_reduce
You're seeing just the function
map_reduce
, go back to Enum module for more information.
Specs
Invokes the given function to each element in the enumerable
to reduce
it to a single element, while keeping an accumulator.
Returns a tuple where the first element is the mapped enumerable and the second one is the final accumulator.
The function, fun
, receives two arguments: the first one is the
element, and the second one is the accumulator. fun
must return
a tuple with two elements in the form of {result, accumulator}
.
For maps, the first tuple element must be a {key, value}
tuple.
Examples
iex> Enum.map_reduce([1, 2, 3], 0, fn x, acc -> {x * 2, x + acc} end)
{[2, 4, 6], 6}