module Enumerable

def without(*elements)

=> {foo: 1, baz: 3}
{foo: 1, bar: 2, baz: 3}.without :bar

=> ["David", "Rafael"]
["David", "Rafael", "Aaron", "Todd"].without "Aaron", "Todd"

Returns a copy of the enumerable without the specified elements. 
def without(*elements)
  reject { |element| elements.include?(element) }
end