@spec find!(Enum.t(), (element() -> any())) :: element()

A variant of Enum.find/2 that raises an exception when no matching element is found.

@spec find_value!(Enum.t(), (element() -> any())) :: any()

A variant of Enum.find_value/2 that raises an exception when no matching element is found.

@spec map_with_context(
  Enum.t(),
  context(),
  (element(), context() -> {element(), context()})
) :: [element()]

Updates items of an enumerable with the given function, depending on context. Context can be any.

The function fun takes item and context as arguments, and must achieve 2 purposes:

1. Update an item according to current context
2. Produces new context for next item

then, return both as tuple {new_item, new_context}.