# File lib/ruote/util/lookup.rb, line 37
  def self.lookup(collection, key, container_lookup=false)

    return collection if key == '.'

    key, rest = pop_key(key)
    value = fetch(collection, key)

    return [ key, collection ] if container_lookup && rest.size == 0
    return [ rest.first, value ] if container_lookup && rest.size == 1
    return value if rest.size == 0
    return nil if value == nil

    lookup(value, rest, container_lookup)
  end