DM collection update bang vs _update.rb

class Collection
  def update!(attributes)
    ...
    model = self.model
    dirty_attributes = model.new(attributes).dirty_attributes
    if dirty_attributes.empty?
      true
    elsif dirty_attributes.any? { |property, value| !property.valid?(value) }
      false
    else
      unless _update(dirty_attributes)
    ...
  end
end

class Resource
  def _update
    original_attributes = self.original_attributes
    if original_attributes.empty?
      true
    elsif original_attributes.any? { |property, _value| !property.valid?(property.get!(self)) }
      false
    else
    ...
  end
end