What does a double * (splat) operator do
ruby, splat
Solution
Ruby 2.0 introduced keyword arguments, and `**` acts like `*`, but for keyword arguments. It returns a Hash with key / value pairs.
For this code:
def foo(a, *b, **c)
[a, b, c]
end
Here's a demo:
> foo 10
=> [10, [], {}]
> foo 10, 20, 30
=> [10, [20, 30], {}]
> foo 10, 20, 30, d: 40, e: 50
=> [10, [20, 30], {:d=>40, :e=>50}]
> foo 10, d: 40, e: 50
=> [10, [], {:d=>40, :e=>50}]
Problem
Have you seen a function declared like this? ``` def foo a, **b ... end ``` I understand that a single `*` is the splat operator. What does `**` mean?