module Hashie::Extensions::DeepFind

def deep_find_all(key)

options.deep_find_all(:address) # => ['123 Street', '234 Street']
options = {users: [{location: {address: '123 Street'}}, {location: {address: '234 Street'}}]}

a key and returns all occurrences of the key.
Performs a depth-first search on deeply nested data structures for 
def deep_find_all(key)
  matches = _deep_find_all(key)
  matches.empty? ? nil : matches
end