The rest of keyword arguments 🍕

Sometimes you pass some extra keyword arguments to a method that doesn't handle them and you get the error ArgumentError: unknown keywords: ....

You can just use ** as the last argument to ignore the rest of the keyword arguments:

def make_pizza(cheese:, sauce:, **)
  puts "Making pizza with #{cheese} cheese and #{sauce} sauce"
end

make_pizza(cheese: 'muzzarella', sauce: 'tomato', chocolate: 'white', syrup: 'mapple')

=> Making pizza with muzzarella cheese and tomato sauce

You can also give it a name to group them:

def make_pizza(cheese:, sauce:, **rest)
  puts "Making pizza with #{cheese} cheese and #{sauce} sauce"
  rest.each {|k, v| puts "#{v.capitalize} #{k} is not good for you"}
end

make_pizza(cheese: 'muzzarella', sauce: 'tomato', chocolate: 'white', syrup: 'mapple')

=> Making pizza with muzzarella cheese and tomato sauce
=> White chocolate is not good for you
=> Mapple syrup is not good for you